I think it's more about keeping this forum one of the few places where you can have open minded conversations that don't delve into hivemind guided flamewars. Granted, I don't know what got warned or the reason.

Anything approaching nuance on other forums gets downvoted to oblivion and attacked if it doesn't fit the particular echo chamber it's in. That just reinforces the echo chamber. HN has to do quite a bit to preserve the culture and keep it from devolving into something like those other places.