Disagree, there were, possibly still are, good ones. A handful around mushrooms cultivation, food preserving, food fermentation and personal finance specific to my country come to mind, lots of high quality content.

But I know what you mean. I think it mainly happens once specific subreddits started going mainstream, often with an influxnl from facebook people. Out of all the fermented stuff, the kombucha one made my eyes bleed due to its popularity. Half the posts where new people asking if they had a mold problem, the other half was existing members posting "read this before posting, this is what mold looks like", but they were obviously ignored lol