The Russians built arguably the best tank of WW 2. The T-34. Followed by the German Tigers and panthers, followed by the US Sherman.
No, we were lucky that the Germans couldn’t build enough Panthers. They were the best tanks in the world up into the 50s. Best optics, armor, and, after Kursk, the best engine/transmission setup, and the main armament would blow holes in anything we or the Russians had until they came up with the JS 1s and 2s, and, we had the M26s.
Had the Tigers had better speed, they could have been the best. They DID have the 88s installed after all.
The Sherman’s and the T-34’s thing was numbers. The panther could kill off 10 of the other tanks to every 1 of the panthers killed. But, if you have on a couple of thousand Panthers, and, the Americans have 24000 Shermans, and, the same for the T-34, you can’t win. Numbers are the best defense.