To elaborate a bit on the difference: many of the ‘weird’ books mentioned here play with the form and the sequence, i.e. they tie the medium into their weirdness—and thus depend on it. The reader is presented with a complex piece, through which they must struggle to get more of the message.

‘Codex’, to my knowledge, doesn't do such tricks and is a rather straightforward book of illustrations—the difficulty is only that its contents aren't readable at all and the illustrations are completely foreign to our world. Unless you know its language, there's just no way for you to get any of the writing.

The former kind of books are high- or mid-brow cultural exercises, whereas ‘Codex’ is a pure surrealist dream.

Opening the article, I was actually worried that the author would begin talking about the meaning of the book, but thankfully he went the same route as David Lynch: while telling some secrets of the production, he said nothing about the content.

Arno Schmidt began work in "this" style, culminating with Zettel's Traum in 1970.

https://upload.wikimedia.org/wikipedia/commons/d/d3/ZT_EA_Do...

The Stars my Destination by Alfred Bester[1] is a good proto-cyberpunk example from the '50s.

[1] https://en.wikipedia.org/wiki/The_Stars_My_Destination