The world is probably not as awful as people are making it out to be. If you go strictly by the numbers, the world is a much better place than it was even 10 years ago. It's not without its problems, but in aggregate, it's not worse off.
This doesn't mean there isn't plenty of work to do. In fact, the progress we have made as a species wouldn't be possible if it weren't for the people who have taken up the cause to advance us. I don't know what really motivates people to devote energy to world improvement. For me, at least, I know it was easier when I was in college, when my biggest concerns were skating by to pass classes, obtain beer and hope that there were girls who wanted to play with my dingdong. There was plenty of energy left over to change the world.
Life gets a little more full over time. Career, relationships, children take up significant portions of that energy. I find that with age, I'm more likely to acknowledge that somethings are not simple. Some problems require complex solutions. Whereas it used to be easy to just say, "Racism is bad, stop racism," now I have to think about the underlying socioeconomic issues, public policy, history and a dozen other things to understand why racism is even still a thing. How do you instigate change when the problem is hard?
Politics in the general sense are like this. The left and right are both in constant blame mode (blaming the rich and brown people, respectively), and the solution is to stick it to those groups. As a rational person, I can't take up either side as a cause. And when people around you treat these factions as a sports rivalry, blindly and almost religiously adhering to one side, there's little you can do to change that. Arguing with people on the Internet gets you nowhere, and trying to win the hearts and minds of people who don't want to consider any bit of nuance is exhausting.
And yet, as a parent, you don't want your kid to grow up in a dysfunctional shitshow of a world that is always hellbent on hating someone. You feel like you have to do something, you know, for the children. How do you do that when the act of parenting and all of that life stuff pretty much expends all of the psychic energy you have?
I don't have an answer, but I think about this a lot. I've often considered that your scope of influence is not really that critical to feeling like you add value to the world, so maybe doing what you can do is adequate. It just feels like an uphill battle.