Why is South Africa a developed country?

South Africa is a developed country, because it was one of the best in the world in politics, economy and military affairs during the white rule. At its peak, the South African rand was higher than the pound. Now that black people are in power, black people also love face. If they come to power, South Africa will become a developing country. Isn't that to say that black rule is not good? This explanation is superficial, but the fact is a joke. What is more true is that South Africa does not actually belong to the ranks of developed countries, but many people still think that South Africa is still a developed country, so you will hear this statement.