because it's a subjective very negative judgement about another human, and in polite conversation one should assume baseline positive things about other humans. it's basically like calling someone an asshole. as HN as a culture of politeness, you apologize first, even if it's justified.
Semantically you are correct, contextually it had the potential to be rude. Words morph and twist in meaning all the time, based on context and individual interpretation. It was not that weird to apologise for calling someone entitled. It is often used as an insult.
Serious question, especially if there’s follow up reading. Where does that principle of assuming baseline good things about the other speaker in polite conversation come from?
I suppose it's an underlying principle of good faith discourse. And good faith discourse is an absolute requirement to have a meaningful conversation or debate that moves (whatever) things forward.
Part of the reason that political discourse is currently so polarised and pushes us towards bad outcomes in our societies (thinking particularly of US and UK here, but I'm sure it applies elsewhere), like the recent riots in the UK, is that so much of it is bad faith, dishonest, assumes the worst of others, casually alienates to score points, etc.
you know how people judge you harshly if you're mean to service employees, I think that colleagues and professional acquaintances will expect the worse out of you if you say bad things out of other people, because they're also in a contextually forced (through work) relationship with you, and if you're a psycho they're going to suffer from it, and they have limited info to judge you from
Why would the word/ term "entitled", need an apology?