I understand that in theory storing the 2FA for Bitwarden in Bitwarden itself can work, but I don't know if I can ever bring myself to store the key to the car in the car, even if I pinky promise myself that I'll never lock all the car doors at once.

This is doubly true because Bitwarden has not been consistent at only asking for 2FA on brand new devices, so it's not even just me that I have to worry about locking the car doors.