Even if it isn’t true, it’s got the feeling of truthiness (1).

I don’t expect it to ever go out of the public consciousness. Like other things that were never real like Stockholm Syndrome I suspect it’s just stuck in the zeitgeist now.

1. https://en.wikipedia.org/wiki/Truthiness

Power poses, imposter syndrome, Stanford prison experiment, marshmallow test...

It seems like the overlap between "real psychological effect" and "subtle enough that it requires research to discover" is vanishingly small. I guess that's not really surprising.