That obviously doesn’t mean a sincere belief in one’s own omniscience, more that the the aura of ‘importance’ bestowed upon things naturally emanate from the centre of the Universe, which is you.
Mind that humans are already pretty much hardwired to do this. Removing external factors of pressure and adding validation in the form of the mass market gospel of ‘find yourself’ just made this a lot more visible.
Funny enough, the people who end up going down to the deep end of this road of finding yourself often find that there is nothing to find, since all your life, you’ve spent it looking for yourself and you never added anything to it. It’s an empty box. You’re the pot at the end of the rainbow that you never thought you needed to put gold into.
From there, people usually split to a few branches. The more transcendentalist amongst us call it the Buddha, the folks with a more philosophical bent call it existential nausea.
The more practical, most of us, go ‘oh.’ and they move on with their lives. Which is probably the most healthy way, anyway.