A lot of people fail to take into account that if the Panther is nerfed, and it stops being built. What exactly do we have left?
The PIV still cannot operate effectively anymore with the Jackson on the field and Zook spam, the Panther for Ost is gated behind large teching costs.
And for OKW, the Panther is all that they have to counter large amounts of medium armor, shreks are still only carried by fragile and crushable infantry, and the JPIV isn't mobile enough to provide support.
The Panther becoming non-viable would only result in the JPIV being mandatory, and Mechanized being thrown to the wasteside, but would leave you with no early game counters to blobbing.
Nobody is saying such a nerf should come without a buff to Raketenwerfer. But your argumentation is extremely forced, think about the tank itself. Allies have a lot of problems on their own and their tank destroyers are still worse. Axis can do the AT without tanks far better because of Panzerschrecks.
Panther is overperforming. If an overperforming unit is nerfed properly, it becomes balanced, not useless.It would then still be built.
Bazooka is utterly useless and not even remotely decent even against Panzer IV. So "bazooka blob" is out of the question. If you do face it somehow, roll over the already poorly scaling Riflemen (unless they have .30 cals) since they are outnumbered and/or undergunned, after all someone needs to carry the bazooka and something needs to be paid for it.
Panzer IV can fight Soviet tanks effectively and Jackson cannot brute force a Panzer IV with panzerschreck and stunning Pak40 around. It would be the same thing with Panther; you avoid the enemy tank, except Panzer IV stands a far better chance because Jackson is far worse than a Panther and Panzerschreck is far superior to something like PTRS or Bazooka.
If you want T3 to be used more , you should first admit that Panther is overperforming. You would then have a case to make Panzer IV better. As it stands you're supporting the notion that there's no way T3 should ever get a buff when Panther is so good.