Oh, I'm sure a lot of those people have been convinced to back these laws out of sincere desire to protect children.
The problem is that those laws are NOT designed to protect children, and the people who convince politicians and the public to support them are NOT doing so out of genuine concern to protect children.
The real, underlying reason why they are being pushed for so hard is to destroy privacy and control people which is going to make everyone but the elite less safe, children included.
Especially if and when we get another Nazi Germany type regime and realize that - oh shit, they have 24/7 overview of where every single person in the world is, what they do, what they think, what their worldviews and identities are.
It's impossible for any of this to end well.
The real underlying problem is that all the mass surveillance companies proposed laws that look like they protect children, and clueless politicians agreed, while the rest of us just shouted on HN about how they're building a digital dystopia instead of proposing any alternatives. The politicians have to choose between banning electronics for children, or mandating ID scans because those were the options presented.