The WSJ article that is linked in the NY Post article is very good. One of things it states is that it is very difficult (if not impossible) to open a door in a submerged car (probably until the water pressure is equalized in the car, right?).
Many drivers mistakenly think that they should try to open their door if their car becomes immersed in water, said Gordon Giesbrecht, a senior scholar at University of Manitoba who studies vehicle-submersion deaths. Due to the pressure of the water, it would be nearly impossible to open a submerged car door.
https://www.wsj.com/real-estate/ange...d=hp_lead_pos7
I do think that cars should have obvious door releases -- I'm not familiar with Teslas at all, but that should be something that doesn't take a manual to figure out.