I do agree that just being nicer is a good idea, even when it's not required, and for largely the same reasons.

Incidentally, I almost crafted an example of whispering all the slurs and angry words you can think of in the general direction of your phone's autocomplete as an illustration of why LLMs don't deserve empathy, but ended up dropping it because even if nobody is around to hear it, it still feels unhealthy to put yourself in that frame of mind, much less make a habit of it.