200 posts down the line and I'm still struggling to see what the point of all this is.
Newsagents and record shop owners - and their suppliers - have always liked easy categorisation. In the 50s, black music was "black and tan"; in the 60s it was "race" music (and, throughout that period, had a separate chart in the US!); the reason being so that record shops could buy what their customers wanted and then group it so that their shop didn't end the day looking like Primark, with stock all over the floor. The categories were offensive and chosen by white suppliers, admittedly - but the reasoning was very clear - give the punters what they want, and suck up the minority's cash rather than let it slip away.
Calling magazines "black" has the same effect. Calling magazines "white", however, would be meaningless, because they cater for a white mainstream. Unless, of course, the implication of "white" is that the magazine is targeted at white supremacists or is forbidden to blacks, in which case the word "white" is meaningful, but racist.
So, yes, in practice, magazines with "white" in the title probably would be racist - but that's not a point of principle, it's an indictment of how society is, so doesn't answer your son's highly principled question.
Still no answer on Jewish Chronicle or Irish Times, claw3 - 3rd time lucky?
And yes, of course non-whites can be racist - but what has that got to do with the world of hair-care publishing?