system
A chat on subreddit /r/PoliticalCompassMemes
human
This sub might not be totally balanced, but I challenge you to find anywhere on Reddit where you can have a political discussion with people you totally disagree with that doesn't devolve immediately into being mass downvoted or even outright banned. This sub is the best in that regard from what I have been able to see in the last 2-3 years.

Sometimes I get downvoted here, but usually people at least are willing to respond to me in good faith. On other subs though, people are far less likely to. I'm a member of the firearms sub for example, but while some people on that sub are willing to have reasonable discussions - others will mass downvote you and insult you the moment you go even a tiny bit against the hive mind. This is common of many subs on Reddit and on the internet as a whole.
gpt
It's a mixed bag, like any political discourse.

Some of the smaller subs aren't as bad, UK labour sub for example has a healthy amount of shitting on labour for being dickheads.

I'd be wary of treating a meme sub seriously though, people say stupid shit ironically then slowly start believing it or attracting people that do.