It’s got less armor than a normal IS4-M and a worse gun than the T-10A that has stabilised gun .
So why is it at the same BR as the T-10A .
My guess is because putting it at the same level as the is3 would be a bit too much.
Still,some BR choices are peculiar to me.
Better armored than it
It’s faster than it
It was fairly balanced back at 7.3 without the BR-471D shell.
At that BR being a bit faster is negligeable , there’s always a faster medium tank than it ,and an even faster light tank.
Yeah faster mediums with not nearly as much armor.
Unless you have HEAT-FS or have a shot at the sides it’s pretty much game over running into an IS-6.
It’s more mobile than the IS-4M and has a better RoF and turret traverse.
So it’s a trade-off.
You are less survivable but gain more flexibility.
You’re comparing a assault vehicle with defensive and long range vehicles, if you own the IS-6 use it on surprise, as stated by others it has superior mobility, use on your advantage.
Its fine as is.