Precisely! Allowing the US to impose this double-standard upon China is no different than any other Unequal Treaty!That assumption doesn't apply to US though.
Arms sales are part and parcel of American foreign policy and statecraft. It would sell or provide weapons to parties in a lot of either low level ethnic conflicts or state level territorial wars - perfect example being current Ukraine war - not to mention the ongoing weapon sales to Taiwan despite Beijing's protests. It requires China to show menacing teeth and sharp claws and start laying down your own rules and laws for a starter. China is no longer a light weight.
Being nice to a bunch of hostile a-holes are pointless unless China gains more, or they cough up a lot of grovelling concessions on a silver platter.
But, hey, we get to keep our Emporer!