AFAIK, every single one of those "built-in navigation/maps" either require the car itself is internet connected (with its own modem), or that you every year get a SD card with map updates to stick into the car.

I guess it's fine in an emergency, but I wouldn't want to use it day-by-day, the live traffic/road closure information in my case ends up saving us tons of time over the year.

It is also OK if you only use GPS 3 times per year.