If I was going into Tank on Tank combat I’m taking the M4 Sherman. Better sights, better visibility, an actual turret basket, better ergonomics, better mechanical reliability, and with the 76mm variant a very capable anti armor gun. As well as far more reliable armor due to high production quality standards. The M4 armor is reliable face hardened. The T34 could be correctly hardened, too hard so that it’s brittle or too soft.
If I was trying to drive a tank to get into a fight, the M4 is the obvious choice due to the much better reliability.
If I had to pick a tank to work on. M4 again due to its easy to repair design.
If I wanted to drive a comfortable tank well that’s no contest it’s the M4. Also it’s an easier to drive tank due to the vastly superior production quality.
So the M4 is a vastly superior weapons platform the only reason they seem comparable is on paper armor thickness and gun. Off of paper they aren’t close. Like pretty much all Russian military equipment they seem intimidating but ultimately are trash. Like how the T 72 got smashed by the M2 bradely and infantry fighting vehicle not even a tank.