The thing people don't understand is that in most oppressive governments, MOST of what the government does is quite acceptable, positive even. The Iranian government definitely also protects women. Even repression is not all bad, or even mostly bad.

And like Iranian laws of public decency, CSAM has it's "oh my god think of the children!" central case that is a reprehensible crime. Nobody disagrees with this. Of course, there's a few cracks already: a number of state governments are trying to classify comic book depictions of LGBTQ, even textual ones, as CSAM. You can even vaguely see the argument, the idea being that this encourages children to engage in such acts.

The problem is that CSAM laws are perfect for this use case. They're absolutely perfect for repression! After all, we can never have a frank discussion of what CSAM is, based on the actual material, for obvious reasons. We can never have the citizenry openly discuss what material gets added to the list, and what does not get added to the list, so we are 100% dependent on politically not-quite-elected people with agendas deciding what's on the list.

Furthermore, one can quickly expose the motives behind CSAM scanning. Is it to help children ... or not? Look at what it's being used for, what these laws effectively do. Obviously it's being used to find children, who are of course in most cases the victim of very minor abuse, or of mistakes, and then placed in the care of CPS. Now you can quickly differentiate motives:

1) if the intention is to help those children, we would make damn sure those children, from that point forward, are treated better than they were at home

2) if the intention is repression, societal control, ... they totally would not care about the treatment of the children found

We all know how CPS treats children. It most definitely does not protect children in their care against sexual abuse, for example. Something like half those children does not go to school at all. They have no real future (yes, thankfully there are exceptions). There is a Netflix series "Young and locked up" that is, among others, about what happens to children who protest their treatment by CPS by running away. Go and look.

Or look at "Short Term 12" where a victim of child abuse is depicted. The victim, nearly adult tries to get out from "protection", constantly explaining how her life at home (presumably/allegedly WITH abuse) was so much better than her environment in CPS, and eventually returns to "home", where she was abused and destroys and rages. It is left in the middle if she wants revenge for abuse ... or is taking revenge for getting her into CPS. In an interview the director points out that this vagueness about her motives, whether they're against abuse or against CPS, is not an accident.

One kid, because he's about to "graduate" from CPS (dumped homeless on the street), tries to commit suicide, because of what he knows his future is. In commentary, it is made very clear that the kid is correct about his future.

And of course, there's many stories in the press that this effectively encourages child abuse. After all, CPS in the US is a horrible punishment FOR CHILDREN, worse than jail in some cases. Which of course means it's net effect is to strongly encourage children to simply accept abuse if they've ever seen CPS in action. And, of course, CPS is completely losing the fight against everything they're supposedly fighting, from sexual abuse to suicide, which of course is completely coincidental. Children FEAR state help against sexual abuse much more than they fear the abuse in the US (not that the situation in, say, France, is any different). And frankly, it's hard to argue this fear is anything but justified.

So, frankly, you cannot trust government with CSAM scanning, and there's no reason to. It's the perfect instrument of repression, we would not even know if it was used for that, and if you look at the full picture of CSAM scanning, including enforcement, the argument that it's there to protect children is ridiculous.