Everything there except the pak has no business engaging an IS-2 frontally.
Let's get real here, that's like me complaining a T-34 can't pen a KT.
A Tiger wouldn´t have bounced that many shots from a SU-85, Zis and T-34/85. StuGs with less range than a Su-85 and no turret should actually be able to somewhat reliably pierce through a heavy tanks armor. After all we see 85mms going through everything also.
All of the anecdotal video evidence in this thread is useless. We KNOW the actual values of the armor, and the values of accuracy and penetration of AT weapons. Videos of unlucky RNG RNG add nothing to what we already know. Balance should also not be made on videos of unlucky RNG rolls.
The point was to show that it´s not just uncommon rng bad luck. I have those kind of bounces on a regular basis. Rng dependent but common, very common. And if one can park his tank unharmed in the middle of StuGs, Paks etc and pick them off without trouble, the game experience is bad.