That's no different than saying everyone in the USSR was a Marxist, or that everyone in the US is a liberal.
Those are states. Top-down civilisations that overwrite peoples wishes. They don't need everyone to follow their framework to enforce it, that's what the police is for. Anarchy isn't like that. You cannot force a person to be anarchist. Any anarchist society that exist must by necessity be populated by people that don't follow the statist framework. Who don't follow authority. Who are Anarchist.
The example you gave is perfect. Normal people who did not understand anarchism were too heavy handed with their judgement and thus actual anarchists needed to be found to help manage that society. People who haven't stop their dependence to authority are a problem to an anarchist society, they don't conform to our framework, our culture, our decision making process and our way of life.
Anarchism isn't just a label you put on yourself. It's a culture you pick up. It is a way to look at situations and people around you. Decide things both internally externally. It's a way of life. A way of life that opposes authority.
Anarchism is a way of looking at the world. And I cannot see an anarchist society function without most of the people most of the time acting and living anarcicly. Essentially when I say anarchist I mean someone living in a culture of anarchy. And that culture needs to exist for anarchic social structures to exist.
for an anarchist perspective on this topic: https://crimethinc.com/books/no-wall-they-can-build.