Well, there is a pattern here with rocket artillery:
PW/Stuka: Small target area, only one short salvo, full damage to friendlies
Katy/LM/Cali: Large target area, large number of rockets stretched out over a longer period, basically no damage to friendlies.
So, seems like they are supposed to do different things. The allied pieces can be used to saturate an area while your own infantry can storm in, the axis ones are good at taking out specific team weapons, but not really for area denial.
Now, why all axis rocket artillery is one type while all allied artillery is of the other is beyond me. Might have to do with how the rest of the armies (were intended to) play out...
I see your Point, however wipes are wipes. They remove the unit and its vet from the field the same way, regardless of which faction is a target.
Either all wipes are bad, which resulted in mortar, AVRE and ST changes, or none are.
Selectively nit picking one unit while others share the same problem does not seem to wise to me, especially since blunt generalization of all armies and their performance seems to be the flagship statement of couple of last patches, leaving out exceptions like this one make completely no sense to me.
And lastly, I have yet to see a singular Player at any skill or stat awareness level apply allied rocket arty in that way, it just does not work like that in game(as in is not used in such way since its against common sense).
That is why I wand Mr.Smith specifically to provide reasoning for what seems like completely random change.