Because those are 4th generation MBTs. (Except type 10 that ots already ingame)
Plus it has strong armor (classified but i read somewhere it has 900mm rha) and unmaned turret. Something that needs more modern rounds to counter.
The only way to kill it with current rounds its the lower plate, neck shots not gonna work with this one. And in hull down positions this thing its invincible.
Now this its my balanced perspective, I know Gaijin will add this sooner and almost no counter to it.
Vacuum 1/2 = 900-1000mm pen
Sprinter = tandem 900mm pen + mmw and 12k anti helicopter reach
In addition to whatever anyone else has said.
The devs haven’t even added M829A3 which is a round from 2003/2004 which is 4 years before the M1A2sepv2 was even made. T-14 is a long way off, and so are any rounds that hit harder.
1000mm frontal armor on the crew compartment, pretty sure it’s 600 on the sides, the area around the gun isn’t armored and the hull sides near that area are likely only 100mm. You can ammo rack it, but it’s designed to blow the turret out to keep the crew alive
In order to ammo rack it you have to go through that 1000mm frontal armor and through the crew. Also the turret could not have any armor but thats useless when the turret its empty. Its like hitting a 2s38 turret except it doesnt have the ammo in the turret.
So in conclusion, only way to kill it with current rounds its lower plate and in hull down you will not make any damage that cant be repaired, as so no crew loss or ammo rack