This question was certainly asked during a meeting 30 years ago and the answer was "don't worry about it".

> Why do you even need a car with an SD card slot in order to change the time?

The idea was that time came from GPS and you had a SD card with the update files for the maps and the current tzdata information. Timezones worldwide change ridiculously often and tying that together with the regular map updates makes sense.

Remember these things are from an era where smartphones were barely a thing and so was mobile phone connectivity in cars.