Much of South Africa is theirs. They should stay and keep it forever. Europeans have been in southern Africa about as long as in the Americas. Telling them they should leave is like telling a Connecticut Yankee, in Connecticut, they should go back where they came from.
Things could turn around there as things are turning around here. Read some of what Siener Van Rensburg wrote in the meantime, Afrikaners.
Don't count the Afrikaners out.
The Battle of Blood River is the name given for the battle fought between 470 Voortrekkers ("Pioneers"), led by Andries Pretorius, and an estimated 15,000–21,000 Zulu attackers on the bank of the Ncome River on 16 December 1838, in what is today KwaZulu-Natal, South Africa.