Tbh, I’m active in some modless subs, and apart from the occasional spam or lost redditor it mostly works. r/Arduino (iirc) for example is unmoderated and not exactly small.

People downvote garbage content and it gets hidden fast.

Compare that to e.g. r/showerthoughts which is so heavily moderated that you need a masters degree just to manage to post there without getting your content deleted or r/WiiUHacks where the mods ban you for mentioning the wrong Wii U hacking project (e.g. Pretendo) even though you broke no rules.

The AI moderation is crap as well, but the upvote/downvote system is robust enough to work as a makeshift automoderation system.