+1 You can still roleplay a racist person or a homophobic person without needing to lean on slurs to be "realistic". I personally don't understand why people would need to make that an aspect of their character in the first place, or why that would be fun or add value.
The current way this is dealt with is useful and I think should still be the way to handle the situation, because even if you make the guidelines more strict there are going to be people who were raised a certain way or in a certain area/environment where using those words is normal or a reflex, so if someone makes the occasional mistake there should still be room to kindly remind them that those words shouldn't be used.
Banning it would hopefully limit people using the fact that these things are currently permitted to make people intentionally uncomfortable, like telling an offensive joke with the intent to offend and saying "oh it was just a joke, calm down" and not accepting any responsibility for the effect their words have on others.
