I know it sounds weird but whenever people say 'gay' or f word in an insulting way I just say 'gay is not a curse word'. It sounds super childish, and I never expected it to have results, but it did somehow. I know of multiple people who now say this as well either because they were told themselves or because they heard someone say it. Simple things like that or 'don't talk about women like that' work wonders most of the time.

It's okay to set boundaries even if it's just for their engagement with you. They'd still have to think about not calling women derogatory slurs when talking to you or around you. And chances are they start to think about it when with other people as well.

You're probably not going to erase bigotry all by yourself. Some people stay bigoted and will go above and beyond to show their views. But the majority of people, I feel, can learn from someone like you just standing up and setting boundaries in a (mostly) non agressive way.

This isn't to say that there aren't ways to justifiably defend yourself with possible aggression. It's just that I found that doing it in a mostly calm way will get better results and is far more safe for you as well.