If you are going to make me liable for something then I has to be something under my control. Short of tying my kids up in chains and never letting them do anything there is no way for me do absolutely guarantee that they will never do anything which causes liability. Not only would I refuse to do that it would be illegal and society does not want parents to do that: kids have to learn to control their own behaviour and that means giving them the freedom to do things wrong. Parents have to be responsible but not necessarily liable. If we are taking reasonable measures to supervise our kids online including giving them guidance on how to behave as well as punishing them when they do not then I believe we have fulfilled our responsibility as parents and should not be held liable if one of them disobeys us and libels someone while we are not watching. On the other hand if parents completely ignores their kids, provide no guidance or consequences then by all means find them negligent and hence liable through their act of negligence...but making parents automatically liable for their kids actions under all circumstances is unfair and encourages poor parenting since if means that you can't risk letting them fail. Indeed the only way to be sure would be to ban them from access the net: does society really want that?
Responsibility must mean liability. You can't claim to be responsible for something and then when it goes all wrong, stick your hands up in the air and say "not my fault!". If you are not liable and responsible, then you shouldn't have kids. They are under your control, thats what society has determined over generations to be the appropriate path to raising human beings.
Now, I do agree with you that they are not totally under your control. For example: you can not beat your kids, even if you believe that it is the best way to encourage the behavior out of them that would yield better results. You could say that the state prevented you from administering the discipline you believed would have corrected their behavior and sue the state. But if you need to be that strict with your kids, and feel you need to beat them, and don't have that option at your disposal (as we do not in the US, for obvious and good reasons), then you should be able to reach out to those limiting your choices, and limiting your liability, as they have limited your ability. Thats fair.
I acknowledge things are not that simple. But to say "I have responsibility, but limit my liability", I disagree. By having kids, you assumed that liability, and took the risk. If you are not able to judge, and assess those risks, then you shouldn't be having kids.
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