Please provide the link to the official DJI website that explains everything about the Mavic 4 Pro to US residents. I guess everyone else is confused and you and DJI are on the same page so looking forward to you answering the dozens of confused...
Yes, for the most part these drones have universal software that can adapt to the environment in which they fly like FCC/CE. Therefore you don't need to buy an FCC drone to fly in an FCC airspace. There may be exceptions but DJI has done a good...
None of us know for sure, they're only guesses; some better than others. Whatever they are doing, it is sanctioned by DJI. I'm sure sure if Adorama has publicly said but even that doesn't matter because only a few people there know for sure...