1. Writers and directors use all the accumulated information about what viewers like and not like, extract patterns, and churn out new movies according to the same small set of rules. E.g. first time the main hero is approached to save the world, he/she/it should refuse. Then something bad happens and the main hero agrees to save the world.
This makes all movies and TV series pretty boring and predictable. Everything is written according to some meta-script. And I've read blogs of some writers so I know that such meta-scripts exist.
2. Storm of political correctness and other movements that took over USA, that look totally irrelevant and crazy outside of the USA. E.g. I won't be able to ever understand why historical persons in the movies should be black even if they couldn't be black in that position at that point of history. There're even more crazier examples.
Same reason why I stopped reading american Sci Fi written in the last 15 years. There're passages that are weird and loathsome.
Frankly, I'm happy that it happens. Movies, books, music is a powerful way to influence the people. USA used it successfully to spread its influence over the world. But if they continue pushing all their crazy beliefs down our throats, people start to avoid that.
I have a feeling that it's already happening although I don't know how to prove it. Probably Netflix has the numbers but it would be grossly politically incorrect to publish them. I know that Disney already experience losses from pushing current US ideology in their movies.
It's also interesting to watch what will win: ideology or greed.