Current SU85 vet2 receives big nerf. The change from 0.7x reload to 1.3x penetration is just a cover. Actually, its dps bonus reduces greatly from 1/0.7=1.43x to 1.3x.
In other word, that's 30% reduction for vet 2 bonus, no less.
DPS doesn't matter for much if shots don't consistently penetrate. So, yes, pre-mod vet SU-85 was amazing against mediums, but lacking against heavy tanks; which meant it served largely the same role as the SU-76, which is far cheaper.