[andrei_says_]

There are also spaces which are extremely tolerant to difference of opinion. You can choose those.

r/changemyview is one favorite example for excellent rational discourse on often very controversial topics.

[systematical]

I'll add r/NeutralPolitics to this list.

[collyw]

r/poltics is awful.

Its a Trump hate thread with very little objectivity.

[genghizkhan]

And then there are those which require objectivity which can be cited and followed up upon. /r/AskHistorians is perhaps the best example of this.