If you want to shelter your child from certain sites or content, that is your problem. Take responsibility for your own family, don't ask the entire world to change and give away our freedoms because of your laziness/ineptitude.
If the internet fucks up everyone's kids except your own then your own kids still have to live in that world.
The idea that future generations are individual families private problems is an insidious wrong.
We're in the world together and where possessible should share that responsibility.
No, I have no obligation or responsibility to your child. You can ask me for my voluntary help, but that's it.
I generally don't believe in limiting freedoms because people abuse and/or misuse something. There are exceptions of course, but this is clearly not one of them. Should we limit the amount of chocolate sold in stores because obese people lack self-discipline or because parents cannot control their children?
Take responsibility for your family or don't have one at all.