> (b) Propaganda that has been thundered ... as a lever for avoiding regulation and oversight.

I think the belief in individualism is real and sincere. It is also exploited ruthlessly, sometimes - but not always - by those who are moving in the exact opposite direction. Where's the authoritarian message in an ad telling you to be yourself, express yourself, stand out from the crowd, etc.? I don't think one needs to assume mass deception (including self-deception) to explain Americans' behavior. While I wouldn't reject your theory outright, in accord with Occam's Razor I tend to start with the simpler theory until the case for some other is properly made.