Where to begin on this “study”?
Let's start with the end of the Ice Age. Well, there isn't one. We're still in it. The last glaciation maximum ended, but the world is STILL in the Ice Age. There have been hundreds of glaciation maximums, all followed by sudden, massive warming, and the various pachyderms and mega fauna survived them all. So just what so different about this last one, that whole ecologies of large animals died out so thoroughly—and where they DID NOT die out?
Yep. Mankind. Everywhere mankind appeared, the mega fauna did too. Except for Africa and South Asia. Aborigines hit Australia 50-45,000 years ago, a land of enormous wombats big as hippos, goanna’s the size of dinosaurs, giant kangaroos everywhere. All died out in the first 5,000 years of man's arrival.
Mankind arrives in Northern Europe around 20-15,000 years ago; same thing. Siberia, also, same time frame, same demise of the Mammoth, Woolly Rhino, etc. Mankind arrives in the Americas a few millennium later, then within a few centuries, the mammoth dies out, along with the American horse, camel, giant ground sloth, giant beaver, giant bison, mastodon, short-faced bear, American lion, saber tooth, all now extinct.
And once again I remind you, the glaciers came and went hundreds of times, and all these creatures survived hundreds of cooling and warmings just fine. So what really happened?
Homo Sapiens Sapiens, the worlds premier badass!