Stop focusing on CP/Abuse.
Governments use CP/Abuse to pass legislation, which is immediately used for almost anything other than that. If a government did actually care about child welfare there are many things they could do that would actually help children.
But this law to "protect children" is being passed by a government that is simultaneously cutting services that help children, and also trying to reduce/restrict sex ed that so that it is easier to abuse children, I'm going to say that "protecting children" is not their goal with this law.
As I said elsewhere, any argument for "we need the ability to remotely access the content of a phone" (which is what the law is demanding: silent updates to remove encryption and anything else they "need") equally applies to having a government mandated cameras in every house. That would actually prevent child abuse. It would prevent domestic violence. If such was happening the police could intervene immediately. It would remove he said/she said from courts: you can simply play the video from the home.
By the definition of "no encryption because protect-the-children", mandatory cameras in every room of every house is both acceptable, and also objectively superior to BS anti-encryption laws. You can't abuse or beat your family members in the first place if a camera is watching, but anyone moving CSAM around on the internet isn't going to have a problem getting an actual encrypted channel - all the law does is make your personal communication, banking, finances, etc insecure, criminals are safe. Of course even if someone does use a now insecure communication channel to share their child abuse it's moot: the cameras in their house would have already caught them.
So why screw around with "make everyone (including children) unsafe to 'protect the children'" when there's a much more effective solution that would stop the abuse in the first place?
Also, the UK already passed a bunch of "you don't get privacy" laws in order to "prevent terrorism", and they seem to be used primarily to catch people not picking up dog poop, not paying tv licensing fees, etc which sure as shit doesn't sound like it's terrorism related.
In summary: if a law that would otherwise violate fairly basic rights is being pushed with clearly emotive justifications like "child abuse", "terrorism" you should assume you are being played.
The police do not need more power. They do not need to violate everyone's rights. They need to do their jobs and do actual work with what they already have, and demonstrate basic competence before they get any more invasive tools. Recall the Ariana grande bombing in the UK? Multiple friends and family of the bomber had independently and repeatedly reported them to the UK police. 9/11: multiple US government agencies had all the information needed, but were too busy trying to compete with each other. In addition (tens of, if you look at the US) thousands rape kits that aren't even processed, and weirdly they keep finding serial killers and rapists when. they. just. do. their. job.
Throwing away more of our privacy, when police already have huge amounts of information that they just can't be bothered to look at, is beyond stupid.
Similarly, based on the track record of supporting and aiding child abusers, and cutting support for children, any claims a government makes saying something is to "protect children" is clearly false.