There was an instance of a parent taking pictures of an underage child's penis to show a rash to his pediatrician during covid who got his account hard banned.
That said, I bet there's millions of parents with at least one pic of a naked kid.
My bet is it's quasi-random, but if you get "lucky", nothing short of a extremely senior exec can reverse that decision. So probably we need to behave as if these accounts can just get yanked on a moment's notice at random.
Fastmail is great, btw.