You say: "The world is full of dickheads, Brad. But what that particular dickhead did/said to you wouid not be considered acceptable by most dickheads, because you are a White dickhead. But if said or done to a PoC, it would be perfectly fine with them, because they are racist dickheads."
I get microaggressions all the time. I'm a Northerner living in the Midlands. I'm a man in his 60s with a ponytail and a beard. I'm a Whovian and LOTR fan, and I use polysyllabic words in everyday speech, because they are the best words for what I'm trying to say.
BUT, these microaggressions are, in the main, personal, and reflect the inadequacies of the person using them. The stuff that relies on stereotyping of the North of England is just part of life here. Hakuna matata.
Microaggressions based on race, gender, sexuality etc are another matter. They mean that the person dealing them out has not identified you as being enough of a person to make their insults personal! It means you've been chucked into the box labelled 'Black', 'Queer' or whatever. When a person is not even respected enough to get personal insults, just generic ones, then that is the outside of enough!