the upper hull isnt off limits, the 2A7V’s upper hull is like the PSO’s hull, not like the strv122’s, its “technically” less protected than the 2A5’s upper hull, this bug has already been reported to gaijin and acknowledged. Theres some weirdo spots where you might not pen (the very thin stripes of red in the above picture) but thats mostly because of issues with volumetric. The 2A7V’s frontal protection is still lower than that of stuff like the T-72B3, T-80BVM, and T-90M.
the actual difference in penetration between M829A2/DM53 and 3BM60 is not actually significant enough for it to matter in-game. Between ~550-670mm of pen, there’s little difference in-game (670 because the 2A7V hull beak can also be penned above around ~660mm of pen).
Russian MBT’s havent had to aim carefully for the last 4-5 years lmao. The only tank that was “well armored” compared to russian tanks was the strv122, that aside, even 3BM42 remained passable until relatively recently with the proliferation of 550mm+ rounds.
As long as a bug remains unfixed, its a feature, particularly when any “bug report” gets passed to devs as a “suggestion”, which is the case with all issues with armor of the 2A7V. Also, ive never ever seen the UFP ERA on russian MBT’s not work, nor have i ever heard of this (quite frankly ludicrous) claim before. ERA is much more likely to actually result in rounds being eaten by volumetric shenanigans than anything else in-game.
the Leo 2’s all have a conga line of crew members on the right side of the vehicle (driver/gunner/commander). Because of this, the Leo 2’s one shot area is about the same size, if not bigger than that of the russian T-series. Theres also the fact that the leo 2’s mantlet is one of the rare pieces of armor in-game that creates EXTRA spall, making mantlet shots unusually devastating.
ALSO, talking about survivability is moving the goalpost. Russian MBT’s are more protected, and id argue that if someone actually tested it, western MBT’s frontal 1 shot area is likely around the same size as the russian MBT’s weakspots. The difference is in the fact that if someones wiffs a shot on a russian MBT, theyre likely to do literally no damage. If a russian wiffs a shot on a western tank, theyre still likely to pen, but only to get a mobility kill.