After several foreigners were perturbed by an"mmhmm" response, American TikTokers explained that "you're welcome" actually feels kind of rude.
I was watching a video from two years ago about different social norms and this showed up. Found someone questioning the same eight years ago on reddit (when it seemed less normalized). It feels so weird not being aware of this shift, even as a foreigner.
I feel out of the loop. Not sure if it's me just getting old or not understanding social nuances, but this all feels like people drawing lines and taking sides on something that's going to vary based on cultural background, age of peers, personal experiences and idiosyncrasies, etc. I don't feel like it's a good situation to have two (or more) sides each claiming that it's offensive to them if someone who doesn't know them responds using a different side's preferred response. Kinda puts customer service workers in an impossible situation.
I reflexively say "thanks" when another human does something for me, and I don't particularly care what their habituated response is. Especially for people working customer service, who are just getting through their day and running their script. Mostly people echo the response that they're used to hearing from others, so unless I have some reason to think they're being snarky...??? Your noncommittal phrase of thanks received a noncommittal response, and both parties can move on from the exchange and do something else with their time and energy.
This is every bit a "kids these days" article. You hit it on the nose--it's a generational shift and older people are clutching at pearls. For funsies, there's a piece of ancient Roman writing I came across when studying classics (I'm sorry that I don't recall who it was) that said essentially "young people don't speak Latin right". This is basically a thing as old as time.