(She asked me if I knew her address.) I was taught very early on that SAPERE meant to know a fact and that CONOSCERE meant to be familiar with, as to know a person. When a sentence seems wrong, I’ll often use a translation app and reverse the direction of the translation to se if it comes up the same. Both Google and Deepl use CONOSCERE, confirming the correctness of the sentence. I’m confused here because an address is a fact, a piece of information. Why isn’t SAPERE used in this instance? Are the algorithms flawed? For comparison, I translated, “She asked me if I knew the population of Madrid.” Both apps used CONOSCERE.
I agree with you, that “sapere” usually means knowing a fact, whereas “conoscere” means “being familar with” but the latter one is not only used with persons.
According to my limited experience, my Italian colleagues in the lab usually use “conoscere” when talking about lab procedures or lab equipment meaning “having experience with”.
So the above sentence does not sound wrong to me e.g. in the context of a taxi driver and a customer (Are you familiar with this address?/Do you know how to drive there?)
But IMHO the apps err in your second example:
Using “conoscere” would imply that you know (something about) the whole population. That’s very unlikely.
Only in “She asked me if I knew the population of Madrid. If I would order the restaurants to close at 11 pm, they would take to the streets!” “conoscere” makes sense.
If it is about the fact that Madrid has 3 M people (my guess?) it must be “sapere”.