I agree with you that the essence of the statement you have quoted is not true. I would add that it expresses a radical philosophy which is not rooted in science at all - it is, in fact, a repudiation of natural science. I do hope that someone with a scientific background will assist you in debunking this fantasy.
But I would like to also provide a biblical perspective to evaluate other data with.
From a biblical standpoint, I would observe that God biologically established gender in Genesis 1:27, and only science falsely so called (I Timothy 6:20-21) will contradict that.
As for race, I would observe that most people do not currently use that word the way the Bible does. The word occurs four times in the Bible, and it always refers to a contest between runners - never to ethnicity.
The closest thing to the concept of biological race in the Bible is the statement in Acts 17:26 which says that God hath made of one blood all nations of men for to dwell on all the face of the earth.
We are all one blood - one race - the race of Adam. The visible differences that your author is denying and passing off as social constructs are what the Bible describes with words like nations and kindreds and people. The word nations is the Greek ethnos, from which we get the word ethnic.
So I would phrase it this way: God designed the biology of Adam and Eve to be incredibly genetically rich - so much so that when the 70 nations of mankind (see Genesis 10) dispersed from Babel and began inbreeding, biological distinctions began emerging which adapted them to the various climates where God led them to settle.
Men with big bones and large frames who generated a lot of body heat fared better in colder climates - smaller framed men did better in the tropics. People in equatorial regions needed more melanin in their skin to resist sun damage and skin cancer. People with less melanin in northern regions needed paler skin to absorb vitamin D from the sun’s more oblique rays.
That same verse in Acts 17:26 also says that God determined the bounds of their habitation. God knew which families were best adapted for one region or another, and He orchestrated events so that they would settle in conditions that were optimal for them.
While it is true that these ethnic distinctions are in one sense superficial, they display the Creator’s love for variety and the way that He has fashioned even the families of mankind to have strengths and weaknesses whereby each can serve and be served in mutual love and respect.
Of course, how men choose to work that out has too often turned out to be another story.
I hope these thoughts will help you.