I think the author is severely underestimating just how much people will pay for a physical book on this kind of topic. I really hope that they find a way to get this printed. $60 isn't even nearing what many people interested in this kind of topic would consider "very expensive."
http://markferrari.com/art/digital-concepts/
(I know there are hundreds of others, I'm hoping people might reply and compile a favourites list for you ^_^)
Since I've spent over 4 years now on this, why not dream higher? I think it's worthy to try to make something cooler, of higher quality and cheaper for everyone.
The book doesn't even have a cover yet, so I might hire an amazing artist as stretch goal or something like that. :)
There's a very good chance I would buy a copy. I already have several physical copies of the books Jeremy Parish put out (pdfs: https://gumroad.com/gamespite, physical books: https://www.amazon.com/s/ref=dp_byline_sr_book_1?ie=UTF8&fie...). Felipe, since I saw you're commenting here, Parish may be a good person to talk to (https://twitter.com/gamespite) for advice on the physical publishing. This is also the sort of project he would be interested in.
I would love to do something like the Bitmap Books ( https://www.bitmapbooks.co.uk/collections/all ), which have great quality and a decent price, all funded via Kickstarter.