Isn't that the point? Giving USF some Anchor for the lategame, as you are likely forced to go Artillery to be useful in teamgames as the Pershing can't maneuver and the Jackson is vaporized the second it leaves it's max firing range, they needed this to be playable in larger game modes than 2vs2 where they agression can sometimes be a boon but I believe they pale compared to Soviets going Lend Lease and Brits still with all their nerfs have much better lategame and Commanders.
The point I believe is just that, a strong suitable tank destroyer that can deal with axis lategame. That's fine imo, the issue I see with it is its high mobility. FFs and SU85s have their weakness of being flanked due to slow turret rotation and turretless vehicles. The jackson now does not have that issue. You don't got KT when you're up against an SU85 or a FF unless you're fully prepared on how you're going to counter it, because those tanks are designed to destroy it. While the jackson now can fill that role, the high mobility and relativly fast turret rotation makes flanks on it ineffective, as it can just drive away at a speed similar to the p4 or panther. Now with the HP buff, the RoF of panthers will be their downfall if attempting to flank given that RNGesus decides to favor the axis moving debuff. But the panther issue is their own problem.
TL : DR
I understand trying to fill in gaps in faction design, but if you need to sacrifice entire factions as a result due to "scope" it need to be addressed in the face of the people setting the scope so they understand the result.
TheMachine, Mr. Smith, and Mirgaefla all knew nerfing penals in WBP would push maxim spam, but relic still allowed it to go through.