That's a ridiculous response. If they managed to infer this characteristic from emails, what they would keep is a tool which, given that set of emails again, infer the same characteristics (and theoretically a similar set of emails). They would by no means be allowed to keep the kind of information you described.

What is more relevant is a model which, given characteristics such as "closeted homosexual with a deeply repressed leather fetish", they would be able to infer other characteristics, such as support of particular political candidates, responsiveness towards targeted political or commercial ad campaigns, etc. That's what's relevant here.