[joebiden2]

The point of the USD as a trading currency lies in its virtually indestructible value combined with malleability. If two countries trade in USD, no party will have a surprise later on.

If two countries trade, for example, in Yuan, and China decides not to buy foreign Yuan in exchange for the other local currency anymore, the value is lost (or at least harder to realize and probably incurring heavy losses).

I'm no economist, but that's my understanding. From this PoV it makes sense to make deals in a gold-backed currency as a replacement for USD. Not sure how they want to get enough gold from to really back it up. Could be possible, didn't research that, but seems of by one or two orders of magnitude.