Because Volks aren't infantry and don't counter Jacksons?
Jacksons have 60 range, and they tend to having things between them and the Jacksons that want them dead. Do unsupported Jacksons suck ass? Yes, the same can be said for every TD in the game.
wasn't it listed as getting a damage reduction but didn't actually get it or something?
Personally I don't think its over performing it is essentially a glass cannon.
HVAP rounds still do 240 damage.
JP4 hard counters the jackson and american T4 unless you drive it in backwards or let the jackson behind you when you have a shrek blob and raketens supporting.
You don't need to flank the JPIV to penetrate it, the main gun on the Jackson will frontally penetrate a JPIV 86% of the time at maximum range.
Once upon a time the JPIV was a hard counter to American T4, not anymore.
The m36 is easy to force away if you play well. Remember the whole never lead with armor lesson? Panthers only have 10 less range. That's not negligible, but it's not much considering it's % to bounce and hp pool. The jackson is the only real threat(aside from p47s) to anything bigger than a p4 in the usf arsenal. Boody freaking hoo, I can't Yolo my armor into American lines and come out needing only a paint job. Volks still have shreks and m36 still doesn't have an mg. 2 jacksons will kill a panther as they should. But 1v1 panther should win. Basically it comes down to support.
It's not about forcing it away, it's about being able to fight it without being kited to hell and back. Forcing it away does nothing because it's fast enough to scoot into range, fire, and then retreat while taking only 1 hit.