Their argument is: 28 years ago, Graham wrote a book about this theory (Fingerprints of the Gods) where he used the language "ancient white civilization". Why precisely he used this language may require deeper research, but it was at-least in part because Quetzalcoatl was described in Aztec literature as being white (to my knowledge this is not controversial), and Graham believes that the Quetzalcoatl story isn't a myth or legend, but rather a spoken-word memory of a visitor from this more-ancient civilization.

Part of his theory (which is well explained in the show) is that there are a handful of ancient cultures like the Aztecs who have stories of an "enlightened visitor" like Quetzalcoatl, bringing the knowledge necessary to elevate their cultures into organized society. In other words: these ancient cultures, who are mostly non-white, were "saved" by an ancient white civilization.

Having followed him loosely since then: he does not use this language anymore; certainly not in Ancient Apocalypse.

If, upon reading that, your conclusion is "mainstream academia may actually be out to get him": you're beginning to understand why people like Dr. Hoopes [1] just need to shut up, go outside, and find more actual evidence to disprove him. Slinging insults like that only adds credence to his statement that mainstream academia is out to get him, which by proximity adds credence to the rest of his theories. But, what he would say is: mainstream archaeology is a lot better at insulting and talking than they are at digging; and independent of his theories, there's substantial evidence to conclude this to be true.

[1] https://boingboing.net/2022/11/27/archaeologists-reveal-the-...