But the main BRICS countries have been creating new payment methods for a while now, with a few successes.
Their alternatives to SWIFT is very successful, it's how both Russia and China have made themselves immune to the secondary effects of western sanctions against Russia. However besides the international transactional agreement, only Brazil have proposed an alternative to US currency, but the other nations have no interest in this.
IMHO, it's probably because Brazil is most vulnerable to the US dollar. The economies of China, India, Russia and SA are not as dependent on the US dollar, since they also trade significantly with non-western nations.
Technically it's western hegemony. US alone isn't capable of a global economy hegemony, despite being the largest economy in the western hemisphere. Rather it's always that EU aligns their policy with the US government.
Besides that, I don't think it will happen. Only Brazil is making this proposal, the other BRICS nations aren't interested. They aren't looking to quickly break western hegemony either.
It's clear to everyone that western hegemony is coming to an end, and these larger BRICS nations seem content to let it happen gradually rather than make a direct effort to end it quickly.