Actually I have done a fair amount of research on where this movement is coming from. It stems from the
American Association of Motor Vehicle Administrators. Canadian Administrator are members too. Some, but not all, state MVAs get together to discuss issues facing MVA's. Most recently they have discussed their "challenges" in classifying new types of vehicles. Rather than trying to understand and classify various military vehicles, they have basically said they are all bad because they don't meet some Federal Standards. Put another way, they condemn anything they don't understand. Why do they do it? It make their job easier and it eliminates the need to come up with pesky research and standards, etc. They use a mish mash of Federal Guidelines which, in a number of cases, are not even legally relevant. The fact that they quote only one study is suspect. Incidently, I would request that this study be named. I would contact the primary authors of the study at some point.
What needs to happen is a legal precedent really just needs to be set in ONE of the 50 states that other states will defer to.
Attached is the DMV admin from Oregon's presentation. You will get the feel for what I am talking about.
Notice how a number of states where MV have been banned, that their DMV admin is on the board