I think the core of the problem is that the bad/disallowed question doesn’t just get silently deleted as I described here: How to introduce newcomers successfully? - #28 by Lundin But instead that debate and critique is allowed to be published live in public for all the world to see. No matter the actual rules of the specific community. If you use public shaming as part of the moderator policies, then people get defensive and aggressive as a result.
So it isn’t about what a specific community allows, as much as how you present feedback to someone posting a question which is bad/not allowed.
As for the case of SO specifically, there was also the problem with veteran vs new user expectations. Old users signed up for programming Q&A for professionals and enthusiasts. New users signed up for “teach me programmming”. This situation was caused by the incompetence of SO upper management. Once Atwood left, Spolsky tried to slowly and silently change the scope of the site (to increase traffic/income), without getting the old community on board with that idea. These kind of problems hopefully won’t exist here, as long as there’s some sort of democratic community behind the design decisions.