I always see people blame Hollywood and writers for today’s films but they just make what the majority of public want to see, sadly at the moment that seems to be lame superhero nonsense.
Blame the public for liking bad things
I'd generally blame the accountants at least as much if not more...*
The people that run Hollywood and provide the funding follow the money and the trends and are usually very risk averse, so they see a superhero film doing well, they'll jump to make more, they see a couple of real flops (not the imagined ones) and they'll shy away from them.
IIRC it's one of the reasons you go through cycles of what sort of films get the big budgets, so for a few years it's Bible epics, then it's Westerns, then it's Horror, then it's Sci-fi, then it's Buddy comedies, or Action heros, then it's super heroes.
It's also worth remembering that those people providing the funding often have their own likes and dislikes for genres, there are some fun stories behind things like the making of the Puppet Masters where it was greenlit as a sci-fi, then the exec in charge changed and the new one hated sci-fi so they had to shoot it whilst playing down the sci-fi aspect of a well known sci-fi story so the exec didn't interfere more than he already was.
It's one of the reasons it seems WB/discovery has been so terrible since the merger, the new head guy of the company is a "reality" pusher because that was what made money for Discovery (not the historical stuff, or the nature, but scripted reality shows), so he's quite happy to dump anything that he doesn't like if it might give a short term saving.
Personally the last film I went to the cinema to watch was Dune, and it looks like the sequel might be the first one since then I go to see, I've lost interest in most of the Marvel stuff because it hit a point where it was more like homework than fun to try and keep up with an ever increasing number of films and TV shows that linked together, and the DC stuff never really impressed me much apart from IIRC Suicide Squad and that's mainly because it was a super villain film and more importantly it was fun to watch, shot with actual lighting! and not (as seemed the way with most of the DC stuff) with 15 watt bulbs and everything having to be grim and dark, and gritty (I don't mind grim/dark but it's not really effective when the entire film is like it).
*I'm finding it more than a little hilarious that a film based on a doll questioning her life seems to be one of the biggest hits of the year, if not the last few years, and the reports that there was no option/contract in place to make additional films with the same primary cast and crew if it did well (so if there is going to be a sequel they can basically ask for a lot more dosh based on the performance of the first).