It's the fundamental (and obviously incorrect) assumption that they're some sort of thugs, rather than decent people just trying to do the job they are paid and trained to do, that makes the author a certified douche bag.
I don't find that obviously incorrect. The banality of evil is probably the most important lesson in human nature of the twentieth century, and it makes many kinds of "decent people just trying to do the job they are paid and trained to do" look a lot closer to thugs -- or at best their enablers.
Could he have done what he did in a less abrasive way? Probably so. But refusing to go along with even little infringements on human liberty is an essential part of eternal vigilance.
Take the Nazis. It's not like every German was evil, or even that most Germans were evil. It was the situation and structure that was evil, and the social proof, and a hundred and one other things, that add up to decent people doing monstrous evil.
Character really doesn't matter for as much as a lot of people like to think. Almost everything people do comes down to their incentives and their situation, from the lowest thug to the most noble statesman. Ascribing flaws or nobility to character is a way of personalizing these situations, often to justify treating people with very few options with harshness and cruelty, while rewarding people in the position to do good with social standing and wealth, etc.