Instead of arguing math and semantics, could we find examples?
Otzi the Iceman and King Tutankhamun & family have had dna analyses. I've tried but haven't found what I'm looking for.
My thought is whether these analyses of ancient dna show differences from modern dna. Does Otzi from 5,200 years ago (guess 260 generations) have alleles that don't exist in modern times? Does he have more chromosomes and/or functioning genes?
One site I did find seems to say that Otzi is pretty much the same as modern people.
OTZI, THE ICEMAN | Facts and Details
The genetic results add both information and intrigue. From his genes, we now know that the Iceman had brown hair and brown eyes and that he was probably lactose intolerant and thus could not digest milk’somewhat ironic, given theories that he was a shepherd. Not surprisingly, he is more related to people living in southern Europe today than to those in North Africa or the Middle East, with close connections to geographically isolated modern populations in Sardinia, Sicily, and the Iberian Peninsula. The DNA analysis also revealed several genetic variants that placed the Iceman at high risk for hardening of the arteries. ("If he hadn't been shot," Zink remarked, "he probably would have died of a heart attack or stroke in ten years.") Perhaps most surprising, researchers found the genetic footprint of bacteria known as Borrelia burgdorferi in his DNA---making the Iceman the earliest known human infected by the bug that causes Lyme disease.
That seems to say that human genetics haven't lost diversity.
A different look would be to examine isolated animal populations. I did find what should be a good candidate - Ossabaw Island pig. Spanish explorers dropped pigs off in the 1500s for later food stops. From what I could find, little cross breeding has occurred since then.
http://wildpiginfo.msstate.edu/...aw%20Island-Case_Study.pdf
The pigs are distinctive with small size, upright ears, and coarse bristles. Of interest to medicine is their genetic tendencies to high fat levels. They actually get pre-diabetic similar to humans. Additionally they are very tolerant of salt in their drinking water and diet.
If I understand Faith's proposal, the Ossabaw Island pig is using pre-existing genes that are now active due to the deletion of genes used by other pigs. To show this, comparisons with ancestor breeds would show no new genes in the Ossabaw Island pigs.
I tried to find comparisons of Ossabaw Island pigs with their presumed ancestors - Canary Island and Iberian pigs. Pretty much all I learned is that I don't know anything about biology and genetics.