Same reason no one recommends Norway for a sunny vacation. It's simply not relevant.
Incorporating BRICS is difficult and bureaucratic. In most cases, foreigners or non-residents face extra difficulties on top of the already opaque bureaucracy.
They are high tax jurisdictions.
Banking in Russia wasn't too bad before the sanctions. Banking in South Africa isn't absolutely terrible but I know people who would rather lick car batteries than bank there.
The rest are terrible. Have fun moving money across the border and exchanging foreign currencies in and out of India, China, and Brazil.
No.
Probably because very few people actually want to live there, compared to the most popular options.