Maybe the author was immature. That's great. Let it remind you what it's like to be young and so excited about something that you'd write a book about it. This book is great.
Something that might be worth noting: two minutes of googling didn't turn up the author's age, but I recall seeing this photo on his website when I bought it some time after it was published in 2008: https://hcsw.org/contact.php
Here's a more up-to-date photo: https://hoytech.com/about
It's possible he was quite young when it was published. If that's the case, then I think the book is all the more a towering achievement. It's abrasive, and it smells a bit of 2000s forum fanboy discussions, but mature people should be able to read past the more opinionated parts and find the gems in the technical treatment.
Or, as we used to call it: "It's all about having had a few conversations with actual people in the actual world".
Many things in LOL are quite opinionated. I don't think it's a distillation of knowledge (like On Lisp), but rather an exploration how far you can take some things (macros).
Also, IMO, the defmacro/g macro defined in this book would have been better defined as a reader macro than as a codewalking macro.
I haven't read it, I have to confess. It would be useful if those assumptions were explicitly mentioned and explained in the book.
Some of the advanced macro stuff is easily outside of the standard and can be still useful, which for example lacks some of the environment features described in CLtL2.
I think CCL still works.
The code here should fix the problems : https://github.com/thephoeron/let-over-lambda
Note, it's been a while since I looked at it so I could have some of the details wrong. The book is still well worth reading to help you understand the possibilities with a programmable programming language, but just bear in mind the various caveats..