I personally haven’t watched much TV or many movies for about the last five years, but I haven’t seen a lot of previews that made me want to watch shows or movies either. Intuitively, I think you’re probably mostly right, although I saw Sinners last spring and thought it was pretty good.
I’ve got a friend on Facebook who’s often complaining that today’s movies are crappy. Now I know this guy because we’ve been in some local plays together, but he doesn’t share my core values. He works at a local TV station that is dominated by Republicans and Trump supporters, and he became one of them when he started working there. So he often complains on Facebook that movies these days are crappy because they’re too woke and that Hollywood is trying to socially engineer us to fit their liberal agenda, etc. It drives him nuts when fictional characters that have traditionally been white or male start being portrayed by nonwhite or female actors lol.