Astroturfing and moderator controlled subreddits have ruined Reddit for me. /r/worldnews is one example of the latter.
Reddit's become a propaganda factory, and it's disturbing. Heavily astroturfed subs are creating an echo chamber effect that's clearly damaging users' mental health. The platform's lax security makes it an easy mark for foreign misinformation campaigns. You can still sign up without even an email address!
Someone analysed a popular post and found that 19 of the top 20 comments were bots.
The Dead Internet theory is all too true.