A lot of this, especially about BRICS not being willing to commit to de-dollarisation during the window of opportunity for it, was pointed out by Patrick Bond last year in his piece titled Samir Amin’s diagnosis of worst-case racial capitalism, centred on South Africa and BRICS. It is well worth reading. I'll provide some excerpts.

In a 2015 Monthly Review essay, Amin (2015) confirmed his negative impression:

“The ongoing offensive of United States-Europe-Japan collective imperialism against all the peoples of the South walks on two legs: the economic leg – globalised neoliberalism forced as the exclusive possible economic policy; and the political leg — continuous interventions including pre-emptive wars against those who reject imperialist interventions. In response, some countries of the South, such as the BRICS, at best walk on only one leg: they reject the geopolitics of imperialism but accept economic neoliberalism.”

In a follow-up, he critiqued the BRICS because economically, “success is primarily defined in terms of the neoliberal ideology, as an example of the success of ‘happy globalisation’” (Amin 2016c, 138).

As we can see, this is very much the case, countries of the global south reject try to the geopolitical interventions of imperialism, such as opposing the Israeli genocide of Gaza, and opposing NATO in the Russia - Ukraine war, yet they accept neoliberal economics, globalisation and dollarisation. Thus, they cannot truely reject the former.

The overarching concern of Washington has been the potential for a major geopolitical bloc to emerge around Xi and especially Vladimir Putin, including BRICS allies South Africa and Brazil, yet the Johannesburg summit did not push that agenda in any obvious way, and Putin was compelled to stay in Moscow because of the International Criminal Court warrant. The BRICS (2023) Johannesburg Declaration did indeed confirm the location of BRICS squarely within imperialism’s multilateral institutions, with explicitly-stated support for the:

“rules-based multilateral trading system with the World Trade Organisation (WTO) at its core... a market-oriented agricultural trading system... a robust Global Financial Safety Net with a quota-based and adequately resourced IMF at its center… [with] increases in the quota shares of emerging markets and developing economies (EMDCs)… including in leadership positions in the Bretton Woods institutions… global consensus on economic policies… the importance of the G20 to continue playing the role of the premier multilateral forum in the field of international economic and financial cooperation… We note the opportunities to build sustained momentum for change by India, Brazil and South Africa presiding over the G20 from 2023 to 2025.”

The simple message here, is that instead of overturning the high table of Western economic power, the bloc is intent on stabilizing and relegitimizing that ‘rules-based order’ – in spite of a glaring contradiction, namely that its underlying ideology, the Washington Consensus, has caused so much suffering in so many low-income BRICS communities.

... As for the BRICS Bank, the main 2023 controversy surrounded the need to increase local-currency lending – because its President Dilma Rousseff confirmed a rise from 22 to 30 percent of its asset base in non-dollar or euro currencies by 2030, a revealingly unambitious objective. The BRICS Bank agreed to Western financial sanctions against Russia (a 19 percent owner) in 2022 due to its fear of the New York credit ratings agencies’ downgrade, bragging that Moscow loans represented less than 7 percent of the bank’s assets.