Don't get me wrong, though. I think the rule is unfortunate because people still want to vent, not because I don't understand why they have it. That said, you can still discuss it in general. Instead of venting about a specific incident, you can describe an issue you have in general terms.
So I still don't see it about pushing away "dissenting" voices, but about not creating drama around specific incidents. Even r/TalesFromDF has to warn people not to encourage negative actions against people.
EDIT:
A nice recent example that I just saw:
https://www.reddit.com/r/ffxiv/comments/r2iizd/send_help/
It seems to have gotten a positive response at the time of this post.