I’m trying to think of what I’ve seen lately in theatres; most of the deeply microbudget fringe stuff tends to get released online, and you only hear about it through word of mouth. (For instance, my friend Tony Ukpo’s After the World Ended, which came out last year and which I’m in briefly, is only available on VHX, although some of his other non-SF stuff is on Amazon Prime.) I liked Upstream Color a lot , and it got a theatrical release, but only because director Shane Carruth distributed it himself.
Basically, the top levels of the film industry are in a somewhat self-inflicted scramble analogous to what the big book publishers are going through, and their strategy is to bet big on flashy big-budget tentpoles where you don’t need to understand dialogue or nuanced social cues (thus more easily distributed to overseas markets), ideally with somebody else (like Marvel) fronting half the budget. I think executives like this strategy not because it makes great money (it doesn’t) but because it lets them perpetuate extremely retrograde gender roles on the grounds that it’ll play better in country X.
It’s not sustainable, but economies of scale make it hard for anybody else to get a foothold on a more than boutique level. Like, even Quentin Tarantino got shut out of some of the theatres where he wanted to run The Hateful Eight, because Disney was determined to get every available screen for The Force Awakens and threatened to pull all Disney movies from theatres that wouldn’t play ball.