> but this is such a perplexing comment.
There is nothing perplexing about the comment it's extremely straightforward.
> You... seem to be upset that it leaves out some subjects.
It doesn't leave out "some" subjects it leaves out a ton of subjects which OP rightly raises. Just about every subject on maintenance.
> without shaming the author for omitting some subjects of your choosing.
The books title contains the phrase "Maintenance: Of Everything"! These aren't a few specialty obscure subjects that were left out. It left out just about everything and OP lists some extremely notable ones. And also calls out important topics for society that have previously been undervalued and appear to be undervalued here.
> How does one get upset that an author didn't include handwashing instructions in a book?
Do you not realize the importance that maintaining of hygiene has played in shaping modern society. To post such an insultingly dismissive reply with a comment like "didn't include handwashing instructions" is absurd.