I don't think South Africa should have ever been added to the list.
But anyways, the whole original idea of BRIC(S) countries is outdated now. The idea was that these were the fastest-growing economic power in a multipolar world to replace the US.
The acronym should probably change, but I'd think there's still room for a demarcation line between "decisively part of the US-led global economic order" and "not part of it". Basically sides in the New Cold War.
Or has Trump's "leadership", combined with the normal progress of change, been so destructive to international norms that it's all just a muddled mess now?