Yes, Steam Greenlight (whatever it's called these days) is a cute idea, but for every gem like the games you mention, there are hundreds if not thousands of crap, minimal effort "games", many of them in a barely working state, which are released there just to make a quick buck or two, either via direct sales, or via the Steam card sales.

Which is also why the Steam curation function is an absolute boon. Let influencers I know trawl through the ocean of games and show me what is good.

You're talking about early access. Greenlight was just a community based moderation process to allow anyone to submit their game without depending on a well known publisher. A greenlit game doesn't have to be in early access. Nothing prevents someone from submitting a completed game.