no, it's mostly that it's 700 pages long (about half the length of the christian bible) and very wide-ranging (also like the christian bible), so you can't put it into a comment on the orange website

howard anton's textbook calculus was foundational for me because it was the textbook i learned the integral and differential calculus from. reading an introductory calculus textbook for me today would not be the same kind of transformational experience because i'd be brushing up on particular integration techniques and theorems rather than encountering a wholly new way of understanding the world for the first time, then struggling to assimilate it into my worldview and skillset. want to know how it changed my worldview? well, if you don't know calculus, i could fully communicate it to you if you make enough effort, but communicating it to you would involve teaching you calculus, and either writing a calculus textbook or persuading you to work through an existing one. you aren't going to understand what i'm talking about after reading a comment on here

and geb is the same way. it was my introduction to the following ideas: formal axiom systems, baroque music theory, symbolic ai, gödel's incompleteness theorem, the foundations of mathematics in general, the formalist conception of mathematics in particular, hilbert's program and the entscheidungprobleme, mathematical isomorphisms, the art of magritte, the music of john cage, the central dogma of molecular biology, the concept of holism, the artistic difficulty of linguistic translation, non-turing-complete programming languages, lucas's flawed argument against the possibility of ai, tarski, quines, and shrdlu. there are probably numerous others i've forgotten. some of these he carefully explains in detail; others he just touches on. about a third of these topics have formed significant parts of my intellectual life in the ensuing decades

quite aside from thus broadening my intellectual horizons enormously, it was a pure delight. the author's enthusiasm for playing in these fields of thought was contagious, perhaps because i was not yet the bitter, jaded cynic i am today. the aesthetic experience of being led through this gallery of wonders is of course not communicable, any more than the experience of listening to bach (or cage, or king crimson, or icp, or system of a down, or myrath, or the beatles) or watching the sun rise on a partly cloudy day

probably if i hadn't run across geb at puberty i would have eventually encountered most of those ideas anyway, and probably encountering it later wouldn't have been nearly so delightful, because explanations of ideas one already understands are rarely as exciting as explanations of utterly novel mind-expanding ideas

so in that sense it's true that 'it is an event in time and is unrepeatable', in the same way as learning anything is unrepeatable. it's true that 'it's somehow unable to be fully communicated about to others [who haven't learned it]', in the sense that you can't fully communicate concepts within any given field of knowledge to people who aren't familiar with its basics. if you don't know what a derivative is, nobody is going to be able to communicate stokes' theorem to you. if you don't know what money is, nobody is going to be able to communicate why microsoft europe is headquartered in ireland to you. and, in the same way, if you don't have any idea what string rewriting systems have to do with mathematical provability, gödel's theorem will sound like crazy moon language to you, though of course geb isn't the only way to become acquainted with those notions

i think the major difference from psychedelic revelations is that many of the things you'll learn from geb are actually true, in an objective, scientific sense, though not some of the 01970s conventional wisdom about how artificial intelligence could be built

hopefully that helps to clarify things for you a bit