For being foreign born, Elon is certainly quite eloquent in his precise and concise native US English.
His native tongue IS English.
“Small correction: I am from a British/English background, not an Afrikaner background (similar to JRR Tolkien, who was also born in South Africa)”
— Elon Musk (@elonmusk) January 3, 2024
South Africa has two “white” cultures - British emigrants and Boers (Afrikaners), who are of Dutch (and French Huguenot) extraction. The British have always spoken English, and the Boers Afrikaans, which is derived from Dutch. But in the last century even the Boers have mostly spoken English.
South Africans also have their own accent, like the Australians have theirs. You can hear a bit of that in Musks speech.