Key word: tactical. As in needing to operate close to the front lines.
It’s a truck that has to be able to travel on dirt without getting stuck in mud, be able to button up to operate in toxic chemical/biological environment, be armored against small arms fire and shell fragments, etc
https://en.m.wikipedia.org/wiki/Heavy_Expanded_Mobility_Tactical_Truck
Our trucks don’t have those capabilities now??
I guarantee you that I can find a mud hole they will get stuck in.