First, race isn't purely a social construct. Obviously race is determined, at least partially, by ancestry and physical appearance, both of which are things science is fully capable of empirically measuring. The common conception of race is probably too flawed and inconsistent to use for scientific purposes, and most contemporary mainstream scientists who study human genetics don't use the word "race", but it's not a completely arbitrary and unfounded concept. If it was, public health offices wouldn't use it to narrow down which groups of people are at greater risk for genetic conditions like sickle cell disease.

Second, even if there is no scientific validity to the concept of race (and there very well may not be), I think everyone knows what the term "scientific racism" means. So I don't see the constructive point in your comment. My point is that there's a distinction between arguing about IQ statistics and burning crosses in people's front yards; I think you're using rhetorical tricks to undermine that point rather than arguing against it directly.