Convincing someone they got duped is forcing them to admit they were wrong. People are too proud to make such admissions, so they will bend their reality until it looks like a pretzel to avoid admitting they were wrong.

Qanoners were emotionally manipulated with horrific (and true) stories of the kind of villains running this world. An emotional person is much more pliable than someone that can maintain their composure and think objectively.

I think a small percentage of them will break away from the puppetmasters, but most of them have invested too much of their lives into Q to give up now, regardless of the evidence (just like vaxxers).