T-72 have a ground pressure footprint between 11,8 to 13 psi (0.90 kg/cm²) depending of variant and M1 have between 13.1 PSI to 13.8 PSI. It's not that much different.That seems like a mistake. By the time the tanks arrive it will be spring in Ukraine, and Western tanks are in general much heavier than their Eastern counterparts. If you thought that T-72 getting mired in mud is bad I shudder to think what will happen to a 60 ton tank.
I don't think they will fare that worst into mud, but nothing on the front will be able to pull them out of there if it happen... so if stuck near the front. You let it there or you risk chaining 2 m1a1 to pull it..