Yeah vehicles I get are supposed to have pretty high damage limits because they are so up armored. So they should be able to last out there for a decent while.
Simultaneously it does feel pretty sisyphean to be able to kill them because 1 person can very much keep a tank online but it takes a lot of people bothering to make a very concerted effort to destroy it.
I don't know where the balance is, maybe the higher leveled classes as the game releases will have launchers or anti-tank weapons that wear them down quicker but it does definitely feel like it is taking a balance pass on.