The “Super Mario Maker Hand Controversy” refers to a “controversy” where Business Insider journalist Ben Gilbert took issue with the new game Super Mario Maker. More specifically, he took issue with the fact that the hand that appeared on screen did not represent his own, but more closely resembled that of a “young white woman”, as he said it (though according to comment sections on the actual article, it is stated that the hand may have belonged to a Japanese girl).
When he asked Nintendo if the hand could be changed in-game, they said it couldn't. This article is proof that gaming journalists are not above cherry picking, misrepresenting information, and making issues out of otherwise innocuous details to stir up controversy for clicks (known by many as "clickbait").
Nintendo later went and said that the hand could indeed be changed in-game, and in a Gamexplain video, the hand had a darker skin tone, proving that this was indeed the case. The article itself was updated with this information.