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Nobody says it anymore
(startrek.website)
I've heard it explained that "hey" used to be more of an urgent way to get someone's attention, rather than a casual "hello" like it is now, so it sounded rude to some older folks.
I thought it was every day life politeness, but I am not native. I would rather expect "the pleasure is all mine, sir" at a 3 Michelin stars restaurant.
To me “you are welcome” comes off as taking credit for something minor and expected. No problem does the opposite. I prefer when people say no problem generally over you’re welcome. And that’s why it’s become more common in a day in age where people are expected to be less servile.