I think you're making an unfair generalization. As a person who lives in the south (in a strongly blue city), I've never encountered this.

No more unfair than the original positive generalization.

Sure, fair enough.

That contradicts my experience. Generally if you're not a dick and don't try to shovel your vegan stuff into people's throats, noone gives a shit about your views or orientation.

People may not talk to you about politics anymore, but anything else - work, kids, cars - is a fair game.

They’re aware I’m not a republican voter and don’t go to church, no one has had an issue still. Is it possible things have changed since you left or you’re being fed the media version of it still and choose to see that? I’ve had respectful disagreements over even vaccination here.

What I am relaying to you is based on personal experience growing up in the lower middle class / poor American south. It's still that way when I go back to visit. As far as "the media version" of the American south goes, I have no idea what you're even talking about. Perhaps you're in a high socioeconomic status bubble and you need to drive 45 minutes in any given direction and re-test your conclusions.

At any rate, I live in the bay area now and I very rarely encounter issues with un-friendliness in the contexts mentioned in this thread. The lack of effusive friendliness that I do encounter for the most part is cultural. Which makes sense, as the bay area is extremely diverse culturally.