I like how the text weasels around having to mention the name of "The famous explorer and former director of the USGS". The Egyptians are a nice touch too.
Thankfully, when it comes to archaeology, there is no shortage of archaeologists getting pissed at this sort of bullshit that denigrates their field and their work.
On top of that, it's gotten armchair experts to damage important sites to "prove" aliens were there or whatever.
If you're interested, this is one of my most cherished books. I got it in college for a class and I've re-read it several times. The author of it actually frequents the group I get most of these posts from, so I got to tell him how much it's meant to me over the years. I highly recommend it.
I enjoyed Al Franken's book, "Lies: And the Lying Liars Who Tell Them: A Fair and Balanced Look at the Right." Your post reminded me of it. Similarly formative in spotting bullshit.
It's right to say there are no Egyptian hieroglyphs, and nothing to be labeled as writing iirc. However, there's ancient art all over the canyon. It's all from peoples who have lived there.