I call this employing tactical empathy and it is the single most important soft skill I learned. It's the only, only effective way to do cross-team coordination, arguably all the way up to C-level to C-level.
Assuming we're using a shared definition of polite, I disagree!
> having or showing behavior that is respectful and considerate of other people.
You can be polite while not facilitating the counterparty in a way that's useful to you but in the short term feels like you're giving up something. People often can't get past that temporary feeling of losing so they don't venture into it.
Was being a bit tongue in cheek, but yes, it depends on your definition of politeness. I’d argue that being genuinely polite, ie being genuinely respectful and considerate, involves the kind of self sacrifice you’re describing. But I also agree that when most people imagine politeness, they imagine what I’d call “superficial politeness”, not “genuine politeness”