There is a wide gulf between not caring about your work at all and getting angry about it. Plenty of us care about our work and the projects we own, we want them to be solid and will stand up to defend them. None of that requires getting angry about it.

There's even levels to anger, and I don't think this author is referring to venting annoyance or expressing politely to someone that they did something wrong. "Oh management randomly cancelled the project you were working on for three years" anyone would get annoyed by that, it's only human. There are plenty of ways people express annoyance. Throwing a fit over it and screaming at your boss or coworkers is just dumb.

(Yes, of course I'd get mad if someone started doodling in the corner of my painting. I'd also get mad if a coworker went on my computer and deleted files at random. These are contrived scenarios that don't apply to 99.9% of regular office work.)

I often hear stories from more toxic workplaces about engineers yelling during meetings, insulting and degrading each other, etc. That's the kind of anger that's unproductive and largely unwarranted unless you're literally working on a life-or-death scenario (which some engineers are, but the vast majority are not).

And that's really what it comes down to. For the overwhelming majority of software projects, it's just not that deep. You mention "artists and craftspeople" but even for them, it's really not that deep. Artists and craftspeople go through tons of abuse, annoying clients, etc. and they don't respond to it by flipping their shit and getting mad. At the end of the day it's just a job, we can value it, but it's almost certainly not important enough to be worth getting angry about.