Nobody really wanted to settle southern africa. The point of the cape colonies was to secure a trading post between europe and india, the expansion in land happened mostly by local farmers doing it off their own bat rather than because that was the plan
The dutch wanted it to secure their own route and the english wanted it so that the french couldnt get it and thus base ships there that would cut off india.
If the dutch had captured mozambique instead (their first choice), I think there is much more chance of noone landing in the cape at all (its not a great natural harbour after all) than England going for it, let alone it becoming a major destination for settlement. Mozambique is a better harbour and allows a more hand off relationship which is more desirable.