> The thing that does seem to have an outsized effect on how people think is their desire to be seen as part of a group and they tend to signal this by repeating arguments they've heard members of that group make. That's where advertising/propaganda has a real foothold in everyone's psychology.

Monkey see, monkey do. This is basically how human society works, and is impossible to stop. The best you could do would be control who people hang around with, but even that is almost impossibly hard to make work.