Doing so politely is effective.

But yeah, it's kind of shocking how often people are like "I hate this thing that person is doing" and I'm like "Have you asked them to stop?" and they haven't. Just... ask? Worse case scenario they say no and you're in the same spot you were.

People prefer to avoid rejection because if you get denied, depending on stability of your self-esteem and feeling of security, you may enter a new reality where you are inconsequential, not loved/respected, and so on. It may end up being a vicious loop of self-fulfilling prophecies and self-hate.

Avoiding such negative consequences of rejection may require a confrontation and possibly very expensive dental treatment (or sponsoring one for the victim of your assault, which it may be interpreted as if you win even if you do not hit first) when it is between two men, and other concerns for personal safety if it is a woman against a man.

(Anecdotally, unfamiliar women seem to have less of an issue asking each other to change their behaviour this way, as do men asking women.)

So, it is more preferable to not complain and instead raise your social status such that you do not come in contact with those people (either real status or at least imagined one, through bottled-up contempt towards those rubes or whatever offending term the context calls for).

I’m not saying it is ideal, just describing why it seems pretty to me obvious how person A would often rather not “simply” ask person B to stop doing something or change something to accommodate person A.