It's all about RNG. The only difference between the T34 and Panzer IV is that the T34 is better against infantry but the Panzer IV is only slightly better at anti tank. The Panzer IV has a better chance of penetrating the T34 than the T34 has a chance of penetrating the Panzer IV, but let's put an emphasis on the word CHANCE because it's still rng dependent.
In a straight 1v1 better between a T34 and a Panzer IV the T34 can still win against a Panzer IV if RNG permits it even though the Panzer IV stands a better chance. I just wish that there is more of a difference between the two, like T34s gets even more price decrease, reduce it's AOE and damage or armor but they would be able to field more t34s per Panzer IV to compesate for it's lack of firepower. Numbers vrs Quality.
actually the ost panzer4 is still technically better against infantry, due to smaller scatter, faster reload, and the mg.
It's just that the allies infantry are bigger and can absorb more loses.