Can an advertiser on FB precisely target any demographic ?
Yes. https://faraday.ai/go/facebook-playbook
Could a pedo or pedo front organization acquire consumer data from the feeds of hairless blond boys from alcoholic single parent households and then direct curated images, text and video exclusively to that demographic?
Yes. With some restrictions.
https://www.bloomberg.com/news/articles/2021-07-27/facebook-reduces-advertising-targeting-for-teenagers
Could an individual or a pedo front organization gain access to web cam, email, and SMS coms of individual members of the target "hairless" demographic?
Only if they know how.
https://www.bloomberg.com/news/articles/2021-07-27/facebook-reduces-advertising-targeting-for-teenagers
FB has some restrictions on minors. However advertising maybe used to persuade the minors to install your spyware for which FB is not responsible and thoroughly condemns.
It was that easy now pedovores who target children on FB go to slam, because patriots are in control.
Image: guy at the far end might be Q.