yeah, you are exactly right. I don't know if films of this sort can really have an original plot anymore because when studios try, the public rejects it and they lose money. However, if you just make a superhero film where you know exactly what is going to happen right out of the gate, it makes buckets of cash.
I blame this on the fact that we have reached a point in history where innovation is not rewarded for the most part and studios making the same films with different characters make hundreds of millions, normally catering to the global market and the ease of translation via soulless action and CGI. In the future I think we will look back on this time as a bit of a "dark age" for film in general.
Your frustration is understandable and I agree.
I believe this is a feedback loop. The more garbage the public want, the more gets produced, it would be a reverse scenario otherwise. Also similarly, the more garbage the studios produce, the more of them people will consume, they have the power to change it. True, might hurt them for a while, but better for art in the long run.
Unfortunately, film is a mode of business for them after all. And no amount of theorizing can't overcome that fact.