Ceci me semble crédible:
quora.com/What-is-the-probability-that-in-a-game-of-chess-the-white-winsI'd note that the 54%-60% percentages are White's scoring percentage, but it doesn't count the percentage of times White actually wins.
In Strongbook 2013, taken from 42,968 top level games, White wins 28% of the games, Draws 54%, and Loses 17%, with a scoring percentage of 55.7%. So 28% is the right answer, depending on what database you choose.
Dans un recueil de 2013 de 42968 parties de haut niveau, les blancs gagnaient dans 28% des parties, faisaient nulle dans 54% et perdaient dans 17%