Your comment makes no sense. She is addressing the argument that "aliens did it," which is a common go-to for people who don't believe Indigenous civilizations were capable of building such incredible works like what we see at Chichen Itza, Uxmal, Teotihuacan, Tenochtitlan, Cahokia Hills, and other archaeological sites.

How does she discredit her criticism of these asinine and thinly-veiled racist beliefs by addressing the key aspect of it (i.e., aliens)? And how is he scapegoating by pointing out its racist?