BRICS mirrors the issue Venezuela is facing.
No buyer base.
In BRICS countries only a few can afford a house, a bitcoin, or consume. Consume is what China sells.
Apparently from what I hear, few people in the USA can afford a house these days also.
Plus you're forgetting China: they are not poor anymore.
Crypto is big in Africa (South Africa, Nigeria and Kenya) so crypto is actually a very viable and interesting solution to a lot of problems with money and exchange rates and monetary fuckery in general...