As long as BRICS remains a trade bloc and not a political bloc then it will be a viable balance to a bullying so-called ally. This could shake up global trade. BRICS is half of the world population with 32% of global GDP in PPP, and is bigger than the G7. Clearly, it will act parallel to the dollar and not replace it, but it should help spread the risk for countries.
Trump's tariffs will accelerate the decline of the dollar's dominance and make more urgent the parallel BRICS payment system.