Agreed. The general sentiment I perceived from HN at the time was that almost nobody was willing to accept Apple's CSAM scanning, even though CSAM had been confronted as an issue before the internet was widely available. I perceived a lot less room for opinions in favor of sacrificing a limited amount of privacy for greater public good, or similar. After the media finished its reporting on the subject, it seemed like there wasn't much more discussion about it, and Apple now seems poised to go forward with releasing its implementation of the scanning anyway at some unknown future date.
The arguments about slippery slopes and potential surveillance weren't as interesting to me as the opposing argument: that a very high level of privacy (not even an absolute level) carries consequences for a specific segment of society by the intrinsic nature of what is kept private, and in the name of protecting that segment of society, the tradeoff is not worth it.
There is also the idea that data on a hard drive can be as damaging to human livelihood as physical contraband, to the point that the vast majority of the world's legal systems, not just those of the U.S., have decided that the data should not exist under any circumstances. CSAM is one of the few classes of digital data that compels the creation of scanning systems for such data on a scale that isn't driven by political ideology, propaganda or similar. It's difficult to imagine how Apple would be obliged and driven enough to implement such a system out in the open and in the name of the public good if the publicly announced reasoning was to scan any other class of data (assuming that Apple can be trusted, at least).