this is again "it takes one to tango" - the people create the incentives the studios follow. movies largely make money with sales volume. this is important; tickets arent more expensive for different movies, its strictly a numbers game (ignoring uncommon deals like toys and video games, etc). according to the first link i clicked, marvel's last movie infinity war grossed two BILLION dollars. you are simply wrong if you think some novel, avant-garde sundance indie is going to interest that many people.
the world is the way people want it to be. this is the tyranny of the majority. if we want non-incentivized things to exist, we're gonna have to invent new socioeconomic theories in this movie thread : )