Comment by YetAnotherNick

> things like prescription medications they take, what kind of contraception they use.. determine that the user might be pregnant

Those are PHI, and Google and other big companies wont dare to touch it with 10 foot pole.

And the other part of your argument is so far into hypothetical space. Just because someone gets ads on certain thing doesn't mean the thing is real. These systems hallucinate all the time.