From the limited experience I have of hearing English spoken by South Africans or even knowing someone is South African (from real life or movies), I find it impossible to really tell when someone is speaking with the accent called South African English (SAE).
"Despite the fact that English is recognised as the language of commerce and science, it was spoken by only 8.2% of South Africans at home in 2001"
I expected (as is borne out by that page), that the great majority speak a native African language (Zulu, Xhosa, Sotho, Tswana, etc.) but I expected a bit more parity (not knowing history well otherwise) between the two colonial languages. But Afrikaans has only 13% speakers, and English only 8% (percentages are for first at-home language not including 2nd languages).
English, the country's lingua franca, is the language of business, politics, and modern communication media, but ranks sixth in home usage.
With that context in mind, what is the SAE accent? Who speaks with that accent? Presumably the descendents of English colonists speak that.
Rather the question I have is, do Afrikaners speak SAE accentless, or is there an Afrikaner accent in SAE, different from a Brit speaking SAE?
That is, did Pieter Botha or F. W. de Klerk the guy in the District 9 movie or Matt Damon in Invictus, did all these people speak SAE with the recognized average SAE accent, or did they speak it with an Afrikaner accent (since they are all Afrikaners at least by name)? My expectation is that Afrikaners and native Africans speak with English with something slightly different than an Anglo SAE accent.