I don’t own an EV, so I don’t know how all this works. But I find this behaviour very weird. The amount of energy needed to move a car is gigantic compared to, well, everything else inside the car. Even without power to move the vehicle, there should be enough charge to open the doors, operate the computer and so on.
When my phone shuts down from lack of power, if I immediately put it in the charge, it will light up the screen to show the battery symbol. So, even if there’s not enough juice to power all the components of the phone, there’s still some charge to turn the screen on to show the battery status. Only if I don’t charge it for a long time is that the screen will take time to start showing me the battery symbol.