I GM 90% of the RPs I participate in, and they tend to last a few years. As such, I can't say I've kept up on what's "meta" for most players, as the quantity of RPs I've participated in is relatively low compared to the time I've been on this forum. Though I will say there's a few differences between the RPs I make now VS the ones I made in the past.

The involvement of AI is a change. I don't consider it a very big one mind you. I've gotten pretty good at spotting AI writing but most don't really use it from my experience. I've seen it show up in other RPs, but my general feeling is that it shouldn't be used to write for you. If you don't enjoy writing you should probably find a tabletop game where you can RP without having to write anything. There are other points/observations I could make but I feel like most of us are on board with not using it to write your posts. I don't see an issue using it to generate images. Regardless if I rip an image off of a website or have an AI design a picture for me I'm "stealing" from artists. I tend to prefer non-AI generated images most of the time just because they don't look so generic. But it's a point of friction with some players, so it's something I try to be upfront about.

What players consider controversial is a pretty big change though. I feel like overall, players have become more open and enjoy socializing with other players. I've never been one to talk about myself too much, but many players like to talk about themselves in detail and often treat the RP group as a collection of friends. This isn't a problem usually, but you can run into some strange situations. On the less extreme end, people's political differences and opinions can surface. Something as trivial as opinions on universal basic income or what it means to be a woman can have your players going at each other's throats. You need to make it apparent that you aren't going to tolerate drama and need to set things up so that these sorts of situations do not arise or you have a way to deal with them. Fortunately, my players have been behaving themselves across my projects as of late

I've also observed that players, especially older ones, have become less adventurous. If you make an oddball RP that's just really strange and out there you can expect nobody to join it. Role players, and especially experience role players, have figured out what they like and aren't going to gamble on an RP they may not enjoy. I like to think of myself as an adventurous role player, but I've also noticed that my participation recently has been squarely in modern-paranormal-anime settings with a brief detour into an anime fantasy setting a few months back. I'll likely participate in something non-anime at some point, but I haven't seen anything grab me for a while.

There has been a slight up tic in superhero RPs very recently. The temptation is to point at The Boys ending or some Marvel IP to be to blame for this development. What people want to play is typically linked to what they see elsewhere. I don't think this superhero fad is going to last much longer though. These things tend to come in waves, and I'm sure they're going to get overtaken by fantasy or whatever else the next big media hit inspires. I say as someone running a psudo superhero RP. But I started mine before it was cool, or something.

What I look for in an RP and that draws me to it, is obviously foremost being interested in the subject of it - I know what I like; sci-fi and mecha RPs, anthro stuff, military and near future military. A small number of fandoms, possibly.
But even then; it needs to be well-presented and written. That doesn't mean flashy graphical flair, that's just icing on a cake. An RP could have the most fabulous graphics ever, but if the actual premise is thin, or inconsistent and rambling without much actually explaining what's going on, what the hooks are and what's going on, then yeah; that's just flash instead of substance.
Give me some substantial lore and world-building to hook me in, give me threads to follow and ideas to inspire me. And also give me firm, but not restrictive guidelines - tell me what kind of characters are expected, what kind of mood and tone we're going for.
It also helps give expectations of what to expect, and makes sure all the players and characters are on the same page.

I'm also in the camp of not really liking sandbox RPs. I've tried a few over the years, but I find them distinctly lacking in any kind of drive or direction. I much prefer a distinct and obvious narrative that pushes things along, if only because it creates a reason for the players all to interact with one another too, and actually do some roleplaying, instead of just pottering about doing random stuff.

GM's being consistent with their expectations and standards helps a lot too. Avoiding cliques or playing favourites with people, and making sure everyone has a fair shake and is treated the same.
Keeping enthusiasm going and communicating that enthusiasm to players is important, as it makes everyone excited.
I haven't joined any RPs for a while now, and I'm mostly just running my own one. I tried joining a couple, but they just trailed off and didn't even really get started. One of them had absolutely insane differences in ability between the characters which made me a bit unsettled as well, to begin with.

Genre wise; there's always fandom RPs and lots of them. There was a period of a lot of 1x1 'relationship' RPs turning up in the general thread areas, but they seem to have been herded back into confinement in the 1x1 section.
Hadn't really noticed the rise in Superhero RPs, but I do see a lot of fantasy ones, and anime-esque high fantasy at that.
I'd personally love to see more Sci-fi, Mecha, 'vehicle'-centric stuff (i.e. fighter jets), anthro/furry stuff and modern or near-future military stuff with a cool sci-fi or 'fantastical' twist. And combinations of all of the previous things.

I think overall, the site has slowed down a lot in general over the years, as other past-times have become more popular, and people want more immediate results for their attention and gratification. Patience and long-term enjoyment are in shorter supply than they used to be, and the immediate reward and satisfaction of things like gaming have taken over. Also it seems like roleplaying by text has moved a lot more to platforms like Discord too (not that I can ever see or find any of these mythical Discord RP servers).
The fact the site also relies on people coming back actively to check it doesn't help sometimes, rather than being notified that they have activity.

Thoughts regarding GMs/GM-Player relations:

- GMs, as any person of authority, have accountability, insofar as being as fair and consistent as possible. I just don't subsrcribe to the idea of GMs being so far above their players as to be beyond resonable reproach. Things like 'hey, you forgot to mention/account for my character['s prior actions] in your most recent post,' should be met with amicability. Requests for slightly more transparency in the RNG, or thoughts on maybe fine-tuning a quickly-concieved resource system, shouldn't immediately draw the scorn of everyone in the room. This goes back to what Sugar and Spite brought up about people not always taking critique well. *Shrugs*

- I've said it before and I'm willing to die on this hill: A GM as the *driving force* behind an RP. The players that join are also important to the story moving forward... and the story literally doesn't happen [in RP form] if no players join. While the moments where an RP just completely wiffs on recruitment are very few and far between, well, the odds may be low, but they're never zero. And respect is a two-way street. Fortunately, I can only think of one GM that I, as a player, felt disrespected by. But honestly, in hindsight, I can also acknowledge that there was plenty of blame on me for not bowing out when I first saw where things were going.

- I will hope that we can at least all agree on this: much like, say, a supervisor/manager in a workplace, not every GM is the same. Some are, generally speaking, amazing as GMs. Some are inexperienced (and hopefully aware of it if they are). Some will try to do too much; others will do too little. And there are some who, frankly, shouldn't be GMing (or simply aren't ready to).

That all being said, I'll confess that my perspectives come from the postion of me being a [tired] adult, who's been RPing for a good while, and really just wants to experience the activity in the most direct way(s) possible, and not have to be worked up by 'chain of command' sh*t the way I am in the "real world"; I've gotten enough "because I said so" to last me a life time and it's still getting delivered. So being able to step into RPs with more loosely structured heirarchies and more communal collaboration is my jam.

EDIT: With regard to the above paragraph: sometimes, one can't be entirely sure if an RP is what one is looking for until one joins and experiences it firsthand.

First of all, I want to thank everyone who's participated in this thread so far! As someone hoping to GM one day, your insight has been very enlightening and I'm definitely taking notes.

On the topic of feedback for character sheets and posts, I understand how receiving critiques in the OOC or even in a server can be upsetting for some. Would it be preferable to instead PM/DM players with any necessary updates/changes/edits rather than addressing things publicly, so to speak?