I think the non-aca meta is often more personal, and that's at the core of many of the conflicts. Non-aca discussions can wind up with people feeling personally attacked, and acafen who are trying to participate in them might've been expecting the same abstract "let's just swap disagreements" attitudes that they are used to in academic discussions.
(And I have a swarm of other thoughts, but limited breaktime at work. I'll get back to this.)