the argument of dying with the tank is pretty awfull really.
if the player wants to exit the vehicle let it exit it!, people say tank battles are hunder of meters away, if the player exit how long do you think he is gonna last until the same tank that burned his crew and tank tear him apart with the MG?
personaly, i have already envisioned the awesonemess of inmersion you have in tanks, seen your crewmates bleeding to dead, the interior covered in smoke and fire, now I wild also like to be able to escape from that hell. Escaping should not be instant, or 100 % effective all the time, it should depend if you are hurt (more time trying to open the hatch or crawl away), what was your position in the tank,etc,etc.
just imagine: you get hit, the tanks gets covered in smoke and fire, you hear screams, THEN the comander (if alive) gives the order to abandon the tank, only then the players controller crew can exit the tank, pushing furiusly the bloked hatches, deformed from the impacts or from the heat, and if you manage to exit, depending on your injuries you may be able to run, crawl of just die next to the burning tank.
then imagine the view from outside, you hit the enemy tank, you see some hatches opening, and the crew trying to exit, but you are too bussy engaging the next enemy tank and you let them live, or you just want to see them pay for what they did to your crew members, and gun them down as they bailt, up to you, doesnt matter to your score, because you get points for DESTROYING A TANK, not for killing a player, you already help your team by remobing a key vehicle to the enemy, the crew without a tank is nothing.
if you manage to escape and get into cover, you can deside if you want to continue the fight, graving an enemy or allied weapon from the ground , or just fall back to the tank spawn and get into another tank.
but GIVE THE PLAYER THE CHOISE, as long as it is realisticly implemented