thats what the article assuming Nvidia could do. Fusing off 4090 defeat the purpose of sending AD102 to China, if they do that they might as well send only AD103.
nothing stop nvidia underclocking 4090 by massive number & sell a clock speed limit 4090. I think Nvidia is going to do the unclocking path, letting the Chinese to OC it.
There is no point fusing off 4090 permanently down to 100CU, that is just wastage of silicon. At that point Nvidia might as well save the trouble, just ship a fully enabled super clock AD103 which is at 84CU, the performance is already very close.