It also reminds me of a recent post-Cambridge Analytica story about FB trying to get patient records, for which they said they "wouldn't get the names of the patients".

Okay, but the only reason Facebook would even get that data is to match it with its users' real names through some of their algorithmic reverse engineering of the data. That data is only useful to FB if it can associate various illnesses with real users on its platforms so that then advertisers can market to those people directly.

Don't fall for the "anonymized data" bullcrap. Google was caught doing something similarly recently, too.