obviously, it would be an 'extreme' option....a remote chance outcome. But since Rep Stefanik pocketed her campaign contributions from Skydio and went on her anti-DJI jihad 18 months ago, every step of the way has included the possibility of an 'extreme' option. All kinds of steps that had a remote chance of happening when all this started have become reality, over and over again
Vic Moss and others, have said over and over that the chicken little's were over-reacting, but guess what...they weren't
so, if the US government insisted that DJI work to ground their drones in the USA, why would they cooperate? Well, for starters, they may not want to tell the US to pound sand because they are unwilling to foreclose on the possibility of reacquiring access to the US market for their drone products in the future. They also might not want to risk the US retaliating by banning sales of the DJI power stations and Osmo cameras & equipment in the US. There is also the possibility that in the tariff wars between China and the USA, it may become in China's interest to ask DJI to cooperate. The DJI portion of the US/China trade balance is insignificant
how could it be accomplished? Well, 
I'm not an expert, but I'd wonder if all DJI would have to do is block the logon procedure that reactivates the Fly app from functioning with ISP addresses in the USA. Within 1-3 months DJI drones in the USA would be effectively grounded
and as I mentioned, in the '
extreme' scenario of the FCC revoking the licenses for all US drones, it then would be a simple step to make flying DJI drones a crime, and use Remote ID as the tool for doing so. Obviously it seems unlikely that there would be any significant enforcement authority or action. But if taking out my 
Mavic 3, with remote ID, and flying it is a crime, I ain't going to do it, no matter how much I disagree with the law