Similar boat: I am fine; everyone else seems fucked.
I suspect this is why those old robber barons had such elaborate social circuits: to keep themselves distracted from the shit going on around them and any role they played in creating said shit.
There's not much an individual can do about the systemic decline. I mean, vote for people who seem like they'll work against it, but that's kind of tears-in-the-sea.
You spent your working years trying to do the right thing & help your country/people on a large scale; you can do that in retirement on a small scale. Look for a mutual aid group, help your neighbors, look for local NPOs who could use your skills. When the system sucks, we have to help each other outside of the system. Remind each other that people are actually, usually, pretty decent, and that our perceptions get twisted by a handful of ragin psychoaths who have somehow gotten to be in charge.
The Radiance of God.