Panzershrecks itself overperforming imo, have you ever seen a axis medium tank destroyed by 1 volley of bazooka? but i have seen panzershreck did many times.
It's not the shreck but volks themselves. They get multiple accuracy bonuses with vet and even after the panzershreck long range accuracy nerf they still hit tanks fine from maximum range.
You can't nerf the shreck without nerfing ostheer. Unless they do it like they did in COH 1 where panzer grenadiers and grenadiers had different panzershreck stats.