- Global warming and how we don't seem to have any plans to a path to hit any of the less-than-apocalyptic warming targets, - Corporate regulatory capture, with more and more wealth going to a smaller and smaller segment of the population while the impoverished fraction grows on the daily, - The rise of right-wing and/or outright fascist authoritarianism across the world, even in countries that would have fought strenuously against it a scant hundred years ago, - This one is a combination of all three of the others (and a lot more), I suppose, but capitalism eating itself and taking a lot of really helpless-feeling people with it.
A lot of things do keep improving, but a) a lot of people never get to see or benefit from those improvements, maybe more than you think, and b) there are these terrible monsters on the horizon and nobody with the power to do anything about it seems to be willing to actually do so. It shouldn't take a whole lot of empathy to project yourself into the shoes of someone for whom shit is the worst it's ever been, nor a lot of creative thinking to realize that there's a whole lot of those people out there.
I think people realize this more than they used to which explains so much of the tech pessimism