And why would that feature rely on a phone in the first place instead of letting the driver change the profile when getting behind the wheel? Or e.g. use a fingerprint sensor or interior camera (which some of the Teslas do have)?

That sounds like some software guy somewhere didn't realize that those seats in the car aren't only for carrying air but that actual people or, gosh, occasional other drivers ride in them too.

Sadly this is rather symptomatic for many things coming out of Silicon Valley (not only Tesla).