AT DPS is highly dependent on the penetration of the weapon and armor of the target.
This is why PTRS isn't the ultimate AT weapon despite having best theoretical DPS.
This is also why Puma is awesome AT and SU-76 is garbage on tracks despite having comparable AT profile.
Yes, jackson is now great, but its DPS is only slightly better then that of Panther, but thats about it when it comes to allied AT sources being better then axis ones in general against most frequent targets.
The allied TD's are not lacking in penetration (40 and 20 less) and the slightly better damage is around 25% for the jackson (and lol at the jacksons vet 1 ability) and 50 % for the su85. whatever they lack in penetration they make up more then enough with much higher dps and being cheaper. and in the okw case being much cheaper. you can easily field 2 jacksons/su85 for each panther.
So saying that the allies lack heavy AT is wrong. In fact its the other way around.
Do you play 1vs1? let me tell you the okw struggles against the is2 simply because they lack the necessary damage to deal with the is2. this is part because of the callin meta but also because their are no fuel caches.