As I understand it, "privilege" has nothing to do with income metrics and what have you. Privilege means that you can assume that society and all its mechanisms will work in your favor. Privilege means that if something horribly unfair happens to you, you can shout about it, and people will listen. Lacking privilege means that, when you shout about it, society will tell you to STFU. Having privilege means you can forget about having privilege. Lacking privilege means you need to constantly worry about losing it.

The reason that a majority of people in a country can be privileged is that, as the majority, they can forget that the minority exists. They can forget that they are the majority.

The minority can never, ever forget that they are the minority.