Indy is great if you like one of the genres where they excel (e.g. rogue like, deck builder, walking simulator, retro, traditional RPG, etc.). However, if you are into genres like modern FPS or open world action adventure then good indy games are difficult to come by.
It doesn't take many to saturate those markets though.
If you're looking for a good indie shooter, look at Diabotical[0]. It's more Quake than Quake Champions was, or even Rocket Arena for that matter. There's plenty of pro-level gameplay on Zoot's stream[1] as well.
Yeah, open world games generally take a large team to create tons of content and a large tools/pipeline team to get said content in engine. So yeah, I doubt we'll see them dominating that space any time soon.
I can't think of a good reason though that there aren't a few very successful indie shooters though.
Mount & Blade series is an interesting counterexample to that, although I'm at a loss as to how define the genre ("feudalism sandbox"?). The first games were very clearly indy, but they capitalized on that success, and Bannerlord is a much more ambitious and polished game.
M&B is actually published by an arguably large company? I don't know where folks put Paradox in the ranking but they're certainly raking in the money with both internal dev & publisher only projects.
And they're making a new World of Darkness RPG for the first time in forever.
It was originally self-published indy, Paradox picked it up sometime during their betas. In 2015, TaleWorlds decided to return back to their indy roots, and got the publishing rights (for all already-released games, as well as M&B2: Bannerlord) back.
