> Something being physically possible doesn't "break" the law, and breaking a law doesn't render that law useless.
No, but the ease of breaking the law does need to be weighed against the costs it imposes on everyone else. Carrying a driver's license is almost a non-cost, and is really only necessary til people hit 28 or so and cashiers largely stop checking.
Needing to verify age online could place very real costs on people. Enabling surveillance is an issue. The chilling effect of knowing that database leaks are going to tie your real identity to your online one is an issue (think the Ashley Madison leaks, but for your old angsty teenager Reddit account). There are a lot of small groups who don't want their membership revealed, like LGBT people in countries with laws against it, domestic abuse victims, support groups for people with trauma, etc, etc.
I don't think I've seen a system that doesn't involve those issues. I'm sure one is hypothetically possible, but that never seems to be a goal of these laws.
So the question is whether restricting social media use by age is worth those drawbacks. My personal values say it's not, but I do recognize that's a value call to some degree and views will differ.
