I've considered the idea of a course for general education that specifically teaches about these psychological traits and the ways they can backfire... a sort of anti-manipulation, bias awareness training camp.

Set up scenarios involving

- fake news about classmates and show everyone how they respond vs researching and being skeptical...

- personal info security vs pwnage / outing / fraud...

- scenarios invoking biases and showing explicitly how they affect decisions and actions

> but a large group of people simply can't reach the level of critical thinking necessary to fully grasp the nudging and political weaselling they are submitted to.

Isn't that exactly the kind of problem that education can solve? Of course that's a decade long process which doesn't happen over night.

Education can somewhat increase the percentage of people we would consider media literate, but there will always be a group of voters who simply can't reach that level of media literacy — some of whom are literally illiterate (a couple of percent in most modern democracies) and some who are literate, but can't (or won't) fully grasp the subtleties of media manipulation. Those are still a lot of voters.