It's largely left up to personal discretion because it's an emotional term (when someone calls somebody an asshole you don't ask "but what defines an asshole" like you're Socrates).

If we're to bring it down to a more objective definition it would be anyone who gets along with the majority of people in the contextual social group. Either because of some sort of neurotypicality or because of some sort of chemical attack wrought upon them by their own obliviousness to what's being put in their water and food. People who lack a soul or people who are just golems. Personally I think half of you are feds and the other half are beneath me. So you're all normies to me too.

It's a choose your own adventure!