I drive a top trim 2021 Mazda 6 and as far as I can tell it doesn't even have any sort of bidirectional data transmission outside of the standard Sirius XM traffic/weather/whatever systems. The internal GPS doesn't even work right since i declined to buy the $400 map pack (carplay is more than good enough for me). I haven't read any privacy policies yet, but my hunch is that there's nothing that bad in them, especially since I'm not even sure how they'd get the data off beyond a dealer service.
Xkit is still actively maintained, albeit by a new team [1]. When I saw this, my first thought was "since when was Xkit a YC company," so definitely an unfortunate name collision.