Why is the M4A2 at 4.3?

Aside from the faster firing rate it offers nothing over the BR 3.7 PZ IV G and the 3.7 T-34. The armor is worse and the gun depression is the same as the Panzers while being on a much taller vehicle(which, IMO, hurts it)

I'm trying to find suitable tanks to play with my buddy who is at 4.0 Russia and I'm a bit surprised this thing is 4.3 while the T-34E of all things is just 4.0