> We don't need the all of society's controls to be flawless

We don't, but we do need them to be at least close to best-effort. This is a nonsense law, implemented in a nonsense way. Clearly nobody cared whether it worked or not, and there's either an anterior motive or it was something the current government (whose idea it was not) couldn't back out of without being labelled "pedo-loving scum!".

Unfortunately, I can't let your examples go without comment either. Age restrictions on the sale of tobacco caused a dive in the numbers of children smoking since those shops absolutely stopped selling to children when the penalties came in. I know, I was one of them and none of my friends could get cigs from shops anymore. As for the height restriction bypass; we're not in Looney Tunes, that's not a thing.