That doesn't mean that you can't be critical! But critical comments need more care—first, to make sure that they're informative, and second to make sure they're free of swipes and putdowns.
https://news.ycombinator.com/newsguidelines.html
I dare say that this is particularly important in Lisp-related threads. A constant caution to those of us here who love Lisp and related topics is what happened to c.l.l., a community that was once one of the richest in computing and then self-immolated because a few people, for whatever reason, decided to normalize behaving like assholes. So on HN, on all programming topics and especially on Lisp ones, people need to treat each other kindly and share information in a spirit of helping, not putting down.
(Also—please don't create accounts to break the site guidelines with.)
I don't think the tone there repelled many people; there must be other reasons, like Python (unfortunately!) replacing Lisp in several domains.
Most newsgroups had a moderated sibling, which was more polite but universally less popular than the main unmoderated one. If the repelled persons had wanted polite discussion, they could have gone there, but they didn't.
Also, I don't think I can really make use of the latter part; it implies that only people who have taught the subject for years are qualified for writing technical books, which - given that I am not a teacher and likely won't be one - gives the resulting vibe of "just give up" without any possible improvements. I can't make any use of that in order to improve my current or future writing.
I get your point on not being a teacher, but I would recommend doing it as blog posts then and not a book, a book implies something much more. Or maybe I’m just old school and not for the current times. After all, there are countless of ebooks of questionable quality on various programming topics.
I'm curious about "a book implies something much more" though. I have seen multiple series of blog posts that then grew to the point where they were actually published as books. What's the difference between the two when one wants to tell them apart via their content? What's this implication that you mention?
For example, books (at least used to) have editors, and reviews by multiple specialists in the field. I can’t think of distinct step between personal writing and something publishing, so I cannot add meaningful comments to your question.
Thanks for the feedback; I'll let my reviewers/editors know, get this fixed in the second edition, avoid doing that in my future writing.
I prefer to listen to what they have to say, especially if it means that I have a chance to make my future writing better in some way. (And I already have one concrete issue that I've remembered and passed on to the people that I've been working on my book with, so it's a net win for me.)