The idea that it’s wrong to appropriate other cultures' customs is perhaps the stupidest idea I’ve seen from the left ever, and even leftists have criticized it (though an old link I had posted a few months ago no longer exists, so maybe that particular leftist was shamed into accepting this nonsense). Oddly enough, I first remember seeing it in a mystery by Michael Innes, probably Sheiks and Adders, which was written in 1982. An Arab character took offense at the idea of non-Arabs wearing Arab dress. Sheesh. Anyway, the idea has not yet really been explored in all its ridiculous manifestations yet, but this little essay makes the obvious point that since basketball was invented by a white male and was originally played only by white males, then blacks who play it are engaged in cultural appropriation and should therefore be condemned by leftists.
Which naturally they won’t do.
Incidentally, in my book on soccer I pointed out (pp. 218-219) that those who were protesting against so much of the traditional canon taught in humanities courses because it represented such a small slice of humanity (that is, mostly white males) never took offense at basketball and America's other sports, even though they were not only invented by white males, but by white males in America during the nineteenth century. That represents an even narrower slice of humanity than was represented by the traditional canon, which consisted of works from many centuries and many countries.