To me, complaints about tone are for critiques that contain phrases like "fucking idiot" and "worthless waste of space" and other such direct insults or attacks.
If something legitimately makes you stop and stare with your mouth hanging open, it is OK to say "this statement made me stop and stare with my mouth hanging open." Phrases like "I am not making this up" are reasonable shortcuts to expressing that sentiment.
Could Mr. Ptacek's review have been worded more kindly? Of course. Do I care? Not at all. It was nice enough. It concentrated on technical flaws rather than personal attacks. It was informative and useful. The tone was just fine.
It's okay if you are writing a story about your personal reactions.
It's irrelevant if you are writing a serious critique, which should be about the content, not about your emotional response to it (assuming it is a critique of an informative work -- obviously, if you are critiquing something as a work of art intended to inspire emotional responses, writing about your response as some relevance.)
It's possible to blend the first kind of story with the second kind of critique, but you have to recognize the different roles of each, do it deliberately, and be exceptionally skilled (the set of people who can do this and produce something worth reading is a proper subset of the intersection of the sets of those who can write entertaining personal stories and those who can write valuable straight critiques.)
That being said, tptacek's review seems pretty focussed on substantive critique with very minimal emotional distractions, so while I disagree with the categorical defense of the individual statements at issue as being appropriate to a straight critique of an informative work, I also think that the charge that the tone was inappropriate and a barrier to reading is overblown considering the fairly minimal level at which distracting emotional descriptions are present in the review.
It's ironic that these critiques of this review are much dumber than the review's critiques of the book, and implicitly hold a fairly off-the-cuff internet comment to far higher standards than a published book that purports to give important and useful advice about cryptography.
Could this review be better? Sure. But who cares?
That said, I want to point out that I think your review was excellent and it's the kind of thing I love coming across. It many ways, it reminds me of the heyday of Usenet. It's great content and it doesn't need to be better. To the extent that it can be better, it's because nearly any work can be made better with additional effort.
A purely "just the facts" version might need a "how bad on a scale of 1-10" or something to get the same information across, and would be less readable.