If you asked 'Would you support weakening encryption in messaging apps if it helped catch some criminals, even though it could make it easier for hackers to read your messages and steal your passwords, bank details, or personal photos?' I'd bet a large proportion of the general population would say no.
But that side never gets explored, or there's an assumption that there's some way of only letting the good guys access the information.
But other people are not technologists. Lawyers think the law is robust enough to determine if someone is a pedophile and only issue warrants for pedophile's data and simultaneously punish anyone who leaks the data of non-pedophiles. Most of the public also believe the police and the law can do that.
When the law is set up to do that, always gets abused eventually, after a time of not getting abused. The public gets outraged and the responsible person gets a slap on the wrist, and the abuse is normalized. In other words, lawyers are wrong and it doesn't work - by our standards. That doesn't stop them thinking it does. Our definition of "you can't do that" is "it's impossible to do that." Their definition of "you can't do that" is "you can do that, but if the police find out, you will go to jail."
1. New power introduced after crisis or scandal, justified as exceptional and targeted
2. Enforcement is patchy or politically difficult. Police either lack resources or big tech platforms don't want to or can't play ball
3. Failure or abuse case becomes public and reported in chattering classes tabloid press
4. Response is not "use existing powers better" but expand powers, broaden scope, lower initial 'targeted' thresholds
5. Cycle repeats
Issue is compounded because you have politicians who will either not understand things or pretend not to understand things.