[bloak]

Yes. And some Quakers were offended by all this unnecessary politeness and continued to use "thou" for a couple of centuries. So English and French used plural "you" for politeness, and so did German at one point, but modern German uses "they" as a polite "you", and so does Italian, I think. So there was an international trend to avoid singular "you" when being polite. But recently in Sweden (1960s/1970s) they've gone back to universal use of singular "you", which seems like a good thing to me, though it's presumably too late for English, despite the holdouts in Yorkshire.

[Tor3]

In Norway the switch happened almost overnight, approximately 1980. Good riddance, the plural polite forms didn't exist in my dialect anyway and it always sounded extremely cringy when somebody tried to use those forms in dialects which didn't have them.

I always say that it's not the words you use which matters for politeness, it's how you say them.