I'll jump in.

I don't know if I'd specifically call any genre my "favorite" since that personally implies to me I would have had to experience it. After all, in a sort of Aristotelian sense having an opinion on it in relation to others would mean I did them, and I only did so many things. Like I haven't done anything romance related and I don't dabble in whatever might arise in 1x1 or arena, so I exclude those. That said I will attempt to describe my opinions on what I do:

- Fantasy/medieval - this pretty much describes my first foray into Roleplaying, as someone who played a lot of Total War. This also informs why I even went into Nation Roleplay. But having had a strong historical bias for most of my life I've been most comfortable here. And often I want to try more Medieval or fantasy settings so I can try on some general concepts or notions I've picked up to see how far I can go with them.

Sci-Fi - I've mostly stumped myself on these because I'm not one for "tech-wanking" or the art of meticulously describing bullshit tech or science. I have tried to use the setting to explore potential future societies but then I stump myself on the sort of conflicts that arise in these cases. Continually redrafting these ideas though I have been trying to steer them more towards an imperfect conception to do just that. To those ends, I need to start joining these RPs to fill in an unrecognized gap people tend to overlook, that being societies that being interstellar may be more or less post-scarcity by force of sheer mass they control, and would be automated probably, but people write as if being not; which seems to me would mean they're heccin' dyspotic so someone needs to have the interstellar anarchists woven in more forcefully than they do. Again, Nation Roleplay things.

Noir - I've sorta tried this. Being a mostly NRP writer I've tried writing noir in my own time and for my own reasons in the controlled space of my own nation. I haven't gone off to join a noir RP in the traditional one-character, one writer approach.

Highschool life/slice of life - Admittedly I use this stuff for shitposting because I can't take them seriously because I carry a perception they're sort of ideal life wish fulfillment so I've infamously joined such RPs to fuck with everyone, at least on older forums.