I wouldn't dismiss the racist element to this decision. Vini isn't just a black player, he's a black player who has repeatedly called out La Liga and Spanish football in general. We've seen how unpopular that made him. He gets slated by all sorts of people now for any perceived slip up no matter how slight. That has to have had an effect on some Ballon d'Or voters.
At the end of the day Rodri is world class but he simply isn't the best player in the world.