He's not saying the race is stupid. He is saying that it is more stupid, an operant he expounds on, revealing his underlying meaning as both accurate and mild. A factual statement is not and is never denigration.
If you and you specifically were the sole member of a race, for instance, his operant would rank your race below that of Black. This would be an observation, not a denigration.
But, if you are not Black, you are the recipient of favorable averaging. Your race would be less stupid than Black, despite you.
> He's not saying the race is stupid. He is saying that it is more stupid
I think the fact that you're reduced to asserting that it's logically possible to assert that a group is "more stupid" without asserting that they are in any way stupid pretty neatly demonstrates my point about comparisons between races with disparaging adjectives being almost tautologically racist.
(The second half of your post is even more pointless to engage with. :)
If you and you specifically were the sole member of a race, for instance, his operant would rank your race below that of Black. This would be an observation, not a denigration.
But, if you are not Black, you are the recipient of favorable averaging. Your race would be less stupid than Black, despite you.
I hope that helps.