It's the second paragraph where it goes off the rails.
She gives us the following to attempt to interpret:
- 'people with significant schizoid tendencies are more common than is typically thought'
- she could be using the term 'introversion', but isn't because:
- she prefers the term 'schizoid' for what it says about the 'complex intrapsychic life' of introverted people
A hundred years ago Kretschmer's 'schizoid' and Jung's 'introvert' had similar meanings, but they have significantly diverged over that time. Outside maybe a tiny community of psychoanalysts, schizoid refers to either a personality disorder or a disordered personality style, and introversion/extroversion are a considered a dimension of all personalities, including healthy ones. So is she using these terms in their modern commonplace senses, or not? She goes out of her way to keep that ambiguous, maybe trying to imply both groups are the same but plausibly not, and works her way through a number of freely selected anecdotes about introspective people she knows to reach her conclusion (point three, above) that was also her premise.
so yeah I'm not keen on it