This is cute, but I don't understand why it's on the arXiv. It's only two pages long, of which almost half is a picture and the bibliography, and as far as I can see contains nothing novel. I love Baez's blog(s) (https://johncarlosbaez.wordpress.com/ and https://math.ucr.edu/home/baez/), and it seems this would have been better served posted there as a post. Am I missing something?
I wonder if Baez put it on the arXiv to make it "citable".
It's in Mathematics -> History and Overview, not Mathematics -> Revolutionary Breakthroughs. It's not claiming novelty, just being very interesting.