Doesn't matter, as many, many people have noted BRICS doesn't exist, and to the extent that it does it's a joke. Two of the countries are actively at war with each other, 2 are falling apart, and the last one is slowly losing a brutal land war.

Better question is how this effects LatAm politics, and that's more interesting. Certainly there's been a drift to the left there, but wild swings in policy are an Argentine hallmark.

Bloomberg article covering Argentina's dollarization when it was first proposed by Milei which has some better info on what that means for Argentina https://archive.is/tef4H IMF paper linked at the bottom of that article is a good read on what dollarization actually means for an economy outside of a political agenda.