I've read in multiple places that this "resetting" is something that is on a list of things to do, but is rarely done. I seriously doubt any person working at the rental place prepping the car for the next use does anything but the most basic/obvious of refreshing. I'm guessing after checking the fuel status and the mileage, they just don't care. I doubt that cars get vacuumed after each rental and only if it's obviously needed.

As the person that is entering their own personal information into a car that you do not own, you absolutely should be the one to remove that data. Do not depend on someone else doing their job. You took the time to add it, so take the time to remove it. It is the only way to be sure.

Most rental cars I get have numerous bluetooth profiles for previous drivers, confirming that the "reset" is rarely done.