Ok I stand corrected, Rob Pike is no fool, I agree the comment seems flippant and a little silly, I guess theirs a few people who shun syntax highlighting.
tonksy also has some interesting opinions on syntax highlighting - not necessarily against highlighting, but taking a more minimalist stance against how highlighting is typically done: https://tonsky.me/blog/syntax-highlighting/
Here's one of the Go creators "explaining" why the Go website lacks highlighting.
https://groups.google.com/g/golang-nuts/c/hJHCAaiL0so/m/kG3B...
https://groups.google.com/g/golang-nuts/c/hJHCAaiL0so/m/E2mQ...