Rumours of the USD's demise have been going on for 30 years. It's still the least dirty shirt in the laundry. Efforts by BRICS nations to set up an alternative are marred by issues like the Indian Rupee being hobbled by capital controls, 20% taxes on gold and trade tariffs. Other currencies are too volatile and illiquid to trade largely.
They could open a gold reserve in each member country where importers and exporters deposit a balance that is adjusted up or down depending on their trades with partner countries but that would be a big step that many participants seem too scared of undertaking.
So for now, the USD's "extraordinary privilege" as the hegemonic currency looks to continue for the foreseeable future. America sliding into unrecoverable debt won't necessarily cause the USD to collapse unless they start printing USD which they're not allowed to do. They have to sell bonds to raise money which just means they'll have to offer higher and higher interest to attract buyers.
NCM Price at posting:
$25.05 Sentiment: Hold Disclosure: Held