Its pretty clear axis, especially Wehr is handicapped against high hp high armor allies heavies. It is akin to making allies td to 50 range/or no pen vet/ap rounds. Imagine playing with this kind of td stats.
The jadpanzer while have the range, its pen is bad, still more worthy than a stug though
This is the whole core of the problem. While the allied factions have no problems with high armour/health units, the axis ones do not have the same capabilities, because they face higher armour units while at the same time having lower pen capabilities on their TDs themselves.