Brexit is example that low educated people should be banned from voting.

This is true.

see: Brexit

As in you underestimate what people will do for the power over others.

Even if it's not misinformation, you can't expect every voter to inform themselves on every issue to know what the best decision is

As in not giving enough credit to politicians?

Uh, you give people in general too much credit. And at the same time you give too little credit to some of them who are willing to go the distance...