The flag, 1912 or thereabouts, was the coming together of the old provinces / states within what is now South Africa and remembering the British and Dutch connections. Note, Lindo, the time it originated and I doubt any thought was given back then to being 'white supremacist' or whatever.

.. Later, for different reasons it did become more symbolic and representative of Apartheid and understandably I take your point, but the flag was, if you like (or not) hijacked by the Apartheid Governments.... don't blame the flag!