Maybe it’s because tech people are prone to binary thinking, but there seems to be the idea that if you can’t prevent a bad thing entirely, then you shouldn’t try to prevent it at all. Or maybe the other way around: if you can’t achieve a good thing completely, then why even bother trying?

While I think you're right that this is a real problem, there's also real costs to a partial solution. It encourages people to see it as a solved problem, disincentivising further reform and giving the impression you don't need to keep an eye on your kid's internet use because the state is handling it for you