Comment by Bjartr

This is actually an area I've been informally studying for several years. Both the "Hi" and the "How are you?" are phatic.

Phatic communication is about establishing social connection rather than conveying explicit information.

Both "Hi" and "How are you?" serve in these cases* to eatablish "this is a friendly, casual interaction" by way of social ritual. If you fail to signal non-aggression in this way then, at least neurotypical people, will be more likely to consider you an aggressor.

I don't struggle or feel bothered by "Hi" or "How are you?". But I do struggle with threading enough phatic praise and appreciation into conversation to maintain the "friendly, casual" status and can get easily start being treated as an aggressor.

* America in particular has "How are you?" as one of these phatic rituals. Different parts of the world have different rituals in different areas of interaction. This can be a cause of friction when moving to a new country and you interpret an unfamiliar ritual literally instead of phatically or misunderstand another's intent because a ritual you expect was missing.