So the world got fucked up because of one cocky, selfish, overly ambitious idiot. Well that's pretty realistic anyway.
I am gonna take a fat guess him and his company arent gonna give up on that project, since from their POV, they dont know what happened and why a terrorist came barging in to destroy everything.
But at the same time, at least the time travelers took Yamasato with them which ensures even if another selfish idiot pops up to mess the world, they can still time travel. Very smart of the author, I'm impressed.
I guess there's a lesson in there: not every dreams should be realized, even if you frame it as "environmentally friendly!"