So my NY registration goes against PA's interpretation:

NYSDMV.com:
Gross Vehicle Weight/Combination Ratings
The Gross Vehicle Weight Rating (GVWR) or Gross Combination Weight Rating (GCWR) of a commercial motor vehicle is established by a manufacturer or qualified rebuilder or alterer of a single motor vehicle when new. The GVWR is placed on a required placard located on the vehicle's left door frame or door. This GVWR represents the weight rating for the unloaded vehicle, plus the maximum load and/or 150 lbs for each passenger the vehicle was designed to carry. This is important because the manufacturer has designed the vehicle to have the power and structural integrity to carry the load and the braking performance to stop the loaded vehicle.

GVWR/GCWR are not used to determine weights on titles and registrations. However, the GVWR or GCWR of a commercial motor vehicle, not the registered MGW, is used to determine the class of driver license required to operate the vehicle. Therefore, amending the MGW on a commercial motor vehicle registration does not affect the type of license a driver needs in order to legally operate it.