Yeah, what's been said already is pretty much on point with my experience. I think I mostly just recognize weird or bad behaviours of mine once I can analyze myself with significantly less ego.

It's absolutely possible while sober, but it can be quite effortless and accidental on a trip. I'm also not so sure all people have these experiences while sober, even if they could - it takes work. Psychedelics can be good at breaking down mental patterns and guards, exposing the things you typically miss or avoid.