the Sherman was a capable medium tank. It held it’s own against the German MK IVs. At the time the Sherman was designed the German MK V and MK VI did not exist. In Korea, the Sherman’s handled the Korean T-34/85s (could also attribute to crew quality)
There is a reason there is this saying about Shermans and Panthers. "A Panther can take out five Shermans... but there is always a sixth Sherman." That references the fact that basic tactics for Shermans against a Panther or other high-grade German tank... was for most of them to attack it head on to keep it distracted... while the last one goes around and shoots it in the back. Any other tactic against them was worthless because your cannon just bounced off their frontal and even side armour.