It is absolutely just the left. The right-leaning spaces, even /r/conservative, do not ban for "wrongthink" unless it is accompanied with obvious contempt or hostility. Conversely, you'll be banned from a number of subreddits simply for posting in /r/conservative or other labeled-right-leaning subreddits.
I don't have any recent information on pre-emptive bans, but years ago /r/conservative had a particular mod (I won't name) who did just that.
Do the same on Twitter (or call someone cisgender) and see how long until you're banned.
(Spoiler alert - I have done both and have been banned as a result)
If you(the general you, not you in particular /nailer)disagree with me, then please explain how any casual observation of the subreddit r/conservative lets someone state that the subreddit does not engage in censorship or banning for wrong think, and with the critical caveat that I will not accept the moderators of r/conservatives statement’s that they don’t engage in censorship as proof on its own
And don’t get me wrong, I’m sure they have a huge brigading problem, again it’s not limited to /r/conservative, but /r/conservative is a laughable example. /r/Republican and /r/Trump are better examples even.