Over the past 5 years r/politics has quietly banned users for thoughtful critical comments devoid of profanity (the proof has been shared elsewhere such as WatchRedditDie), and deleted inconvenient current event posts before they hit 100+ upvotes. The mods leave alone flippant casual unpersuasive conservative comments knowing they'll be downvoted and make conservatives look bad, and censor the thoughtful persuasive ones.

It hasn't been just the downvoting, but as the crowd is thinned, increasingly more bots inflate votes, and those who remain are more deeply steeped in their bias perhaps it will be mainly downvotes from here on out.