The problem is I just don't see how half these things can be done in a effective or shift time span.

For instance in California our governor Jerry Brown has spent like 60 billion on this bullet train yet it's always a decade away.

Shit's corrupt.

That's the thing with Sci-fi, you don't see much kelptocracy or corrupt for some reason.  Or hell even the fact most people won't be these well read academic types, that in history was never the case and it still isn't even with universal education.  I genuinely do believe that even in the time of interstellar colonization you will find folk cultures, corrupt mother fuckers and really, really delusional people with insanely stupid ideas that get lots of people killed.  Also people who think *their* planet is the center of the universe, people who decide to reject all knowledge for the sake of it, people who are so out of touch with reality they believe that the virtual reality world's are the real ones and won't hear any evidence to the contrary...  The idea that everyone having stuff ends wars is not entirely true as you still have the desire of relative wealth to worry about along with the have nots who want to crash the system if they see others prospering more than them.

And some of your ideas are a bit over the top, but consider that some of the tech you mention is still in the labs and the futurist jargon at times can be embarrassing.  Farming on roof tops is common, does that count as vertical farming?  Farming vertically has logistic troubles, but it's just farming stuff in a skyscraper which would take a lot more energy than farming in fields.  Id love to to see it in action though, surely some European country has something like this in the making, right?

Water filtration is already being worked on, though with the rains some time has been bought....  But I wouldn't wait on it still myself.  Issue is that even if you get enough water to drink you still have all the water need to plant crops and such.  Filtering urine out of water I believe would be a good step forward and I honest to god cringed on that one story of the kid who pissed in a water reserve and in response they dumped 58 million gallons of fresh water.  Cringed.