It can work to pay for oil form places like VE and IR. But I agree, trade is so intricate, so layered, it's not going to be efficient to shave a few tenths of an ounce from a gold bar to pay each worker in 50 countries to get a smartphone made.
I'm not about to say "Bitcoin Bitcoin Bitcoin!!!". Yes, I think that asset backed blockchain could be the answer, in a few decades. But after USD and before commodity backed blockchain money, we'd be insane not to bet on CNY as the defacto world currency, once the PRC opens it up properly.