I'm sure a lot of HN commenters would agree that a CSAM detection system with a 13-20% false positive rate should be terminated, but we're not EU regulators. And you've got a sibling comment saying this would be malicious compliance, so even on HN it's not unanimous. Is there an example of a specific EU official, MEP, etc. explicitly stating that tech companies should not perform hash-based CSAM detection or should not perform CSAM detection at all?

Yes? The Pirate Party has MEPs, it’s not exactly difficult to find their quotes. 3 seconds of searching was enough to find the following quote from MEP Markéta Gregorová:

„We can now finally say with certainty that Chat Control 1.0 will end on April 3 without replacement. The European Parliament has sent a clear signal: it is time to put an end to this ineffective and disproportionate derogation from privacy rules. Under the pretext of protecting children, millions of private messages from innocent citizens were being scanned for years without delivering adequate results. This system simply did not work and had no place in a democratic society.“

It doesn’t have to be unanimous on HN. It wasn’t even unanimous in the EUP.

But what it was is legal and democratic. And the discussion in the parliament explicitly included the fact that the companies will either have to stop, or find a different legal grounding.

The companies in this blog post are effectively admitting they are making a choice to go against the law.