The thing about abuse is that, yes, you can ignore it. But it doesn't go away. It often gets worse. And part of the human condition is that you're a person with a brain that can handle only so much abuse before you start unraveling mentally, emotionally, physically, etc.
Yes, in general, it's a good thing to try to ignore random assholes. But when those assholes are in multitudes, they make you their focus and their harassment doesn't stop, ignoring it just makes the problem worse for yourself.
Just making this comment because I once believed the whole "just ignore it" thing myself. I had a relatively rough life and it takes a lot to really bother me, so I could "ignore" it and did. Eventually it gets to you, and when it does, you won't be in a place where ignoring it works anymore.
The lesson I learned was to walk away from toxic situations early. You don't get brownie points for sticking it out in shitty situations, what you do get is deteriorating health.