Apartheid has a very specific thing. Even if we generalise it away from south africa, Apartheid is a system of segregation ensuring one particular population has control of the political social and economic life. It is an intense for of social segregation enforced by a system of governmental statist authority.

You can maybe accuse anarcho-primitivists of not taking into account that a primitivist lifestyle is incompatible for caring for certain people (among those commonly enumerated are those who require advance medical intervention, for example disabled or trans people) - that can be an argument you can have and I'm sure a primitivist would be willing to engage you in that if you came in good faith.

But to accuse them of facilitating a system of apartheid is incredibly bad faith against an anarchist school of thought and, more over, incredibly poor form with regards to anyone who has lived in either the specific apartheid of south africa or in general the victims of the systems of intense racial suppression and segregation which still exist in the world.