This is just as lazy a take as the UK government though.

Many societal problems would be trivial if you could get perfect compliance from the population. You can't, so if you're interested in solving problems you need to be willing to grapple with the world as it is. So far as I can tell online safety has not meaningfully improved since the late 90s - "enforce safety at home" has been the advice for all of that time and it has never worked.

I don't have a solution but "blame the parents" seems to be a very clear non-answer without some plan for how to make creating safety at home more easily actionable.