I think our personality and social intelligence are pretty much established from high school.
I know it sounds depressing for the self-development crowd, but as
@shookwun used to say, "lol at people who think they can reinvent themselves".
And yes, that can also mean accepting your inferiority when it comes to personality and social skills.
Like with looksmaxing, there's only so much you can do, and you'll never turn a shy introvert into an extrovert who's the life of the party.
Of course the two are linked, good-looking people are automatically seen as more interesting, positive and charismatic.