it's not just the angry part. if you say "vizio model xyz phones home such and such information, and here are the logs to prove it", I'll believe you unless I have a specific reason not to trust you as an individual. if you say "the entire TV industry spies on its customers", that's not implausible to me, but I'm going to assume you're just repeating something you've read elsewhere (and I'd rather just read that). it doesn't add any concrete information to my mental model.

I do find that the angry part does correlate pretty strongly with people who can't really back up their sweeping claims or are simply exaggerating.