To continue an example, it'd be saying something like: "Nords are smarter than Bretons." This is a big no no, especially when you'd have to associate certain human groups (with their specific combination of skin color and other physical features) with these bonuses.
They would still be entirely fictional, so the racism argument doesn't hold or do you think "Adventures in Middle-Earth" (a 5E based game) is racist just because it features different human groups with a slightly different ASI distribution?
Sorry, but I really don't see the issue as it's all fictional. Now, if a game would be based on earth ... then I'd understand the argument, but it's not.
People really need to stop dragging real world problems/world views into fantasy.
