So you're just going to ignore the fact that a piv can be countered by REs with zooks
Old argument: AT on okw inf is bad!
Hypocritical argument: it is ok on all allied mainline inf.
That's disgusting hypocrisy.
It's not hypocritical when the inf AT are drastically different and are against different factions all together. If Volks had say, bazookas instead of shreks back in the day it wouldn't of been the worst thing in the world, because bazookas can plink off medium armor and deal less damage. Shreks don't, shreks rarely ever plink on medium armor and do more damage.
Then, when even heavier armor hits the field you'd be hard pressed to find bazookas even penetrating a brumbar or panther unless in high quantities. If they are in high quantities then your opponent clearly has no anti-infantry capabilities. A Panzer 4 can be "deterred" with say, 4 bazookas, not countered. Just as an AT gun deters a tank, but technically doesn't counter it. It only counters it if you lose your tank to said anti-tank weapons. Cuz when it comes to Inf-AT, they have an 8 secondish reload time, that's a long time. The reason panzershreks were so ridiculous were that shreks not only have higher damage, but higher pen leading to alpha strikes. Let's do some math
(medium tanks have 640 health, typically 180 armor)
Bazookas do 80 per, so per bazooka: 80, 160, 240, 300, 380, 460, 540, 620, 700
Shreks do 120 per, so per shrek 120, 240, 360, 480, 600, 720
So even if you had 4 bazookas it would take at least 9 shots ASSUMING none of the shots miss or plink. Add on the 8 second reload time (Where you can shoot the crap out of them). When you say spammed volks, you could easily hit 5-6 volks. Which is just enough to either almost alpha strike or straight up alpha strike a tank.
I agree that guards/penals do pose a certain problem in which they are good against both Infantry and tanks. The upside is they lose to dedicated platforms. Like Guards/penals can't beat true elite infantry, like obers. They also can't do massive damage to heavier tanks.