The German tanks were designed to knock out other tanks. The Shermans were designed to kill infantry, and they did it very effectively.
Do you actually know how tanks work? All tanks are effective against infantry - even the puny Japanese tanks were effective against infantry. But tanks are an anti-infantry weapon only in the absence of other tanks.
The difference was that the German tanks - the Panther and the Tiger - were way too effective against the Sherman and we lost far too many good men because we refused to move more quickly to develop a competitive design. The cold-blooded decision our planners made was that it took more shipping to move heavier tanks and we had the production lines going for the Sherman and we had plenty of men to spare. So they died in a less capable but more numerous tank.
Even the improved 76mm main gun was inadequate against the Panther and the Tiger. It took the British Firefly version with its monster 17-pounder gun to finally defeat the heavier German tanks.
Try not BS somebody who knows his history.