You miss the point: as you note, there's a sexist behaviour observed in some men. You have to choose a word to describe this behaviour. If you choose a word that suggests that a whole category has that certain behaviour, then you are being sexist.

Let me show that with a simple example.

Some women are always complaining and whining. You have to find a word for this behaviour. If you choose a word (femmwhining, maybe?) that implies that all women are always complaining and whining, then you are being sexist.