Topics are "curated" at best and algorithmic garbage-in-garbage-out at worst. Subreddits are moderated, often by people with at least a passing familiarity in the subject matter. Moderation allows on topic discussion without putting a gatekeeper behind exposure, as long as posters follow the rules.

I tried following the webdev topic and it's just interaction-baiting bullshit. Like loops vs reduce. Or "offend a webdev with 3 words".