Ah, I see. I guess that's another example of whether or not one extrapolates the PC rules out to say something about the population at large. Even if floating ASIs were the default rule, and more players chose to play elven barbarians, I wouldn't conclude that elves as a group are more likely to be barbarians, and wouldn't populate my worlds with elven barbarians, and would ask the player of an elven barbarian to come up with a good background story.
Again, just a different approach.
(edit) however I will grant that choosing elven barbarian is less likely to be novel/original from the point of view of other players. It's no longer "against type" from a player perspective, even if it would surprising/unexpected/rare within the game world.