I mean, this is a constant problem with legislation. This, and enforcement.

You make it illegal to do something because we need to protect the children and only those willing to break the rules will be able to deliver on the thing that people want.

This already happened recently to smoking, specifically vaping, and I'm all too familiar with the arguments. But if I can take an example from vaping.... They wanted to outlaw flavors, and largely failed. Bluntly, there's already laws, which lack any semblance of effective enforcement, which prohibits people who are underage from buying, owning and using any tobacco products.... More or less, depending on your specific country/state/province/region/county/whatever. But history has shown that tobacco products end up in the hands of underage people regardless of this. Whether because the cashier at the local smoke/vape/whatever shop or convenience store or gas station or whatever, didn't give enough of a flying fuck to deny someone because they "did not have their ID with them" or didn't even care enough to bother asking for it. I can't blame them, pissing off a passing customer who might be armed, could be violent, may have anger, violence, or homicidal issues, just because some fat fuck behind a desk says no, risking the rare chance that the person could be participating in an investigation which will result in a "hefty" (though not hefty) fine at worst, one which they won't have to pay, doesn't really give the best motivation for giving any shits about the law.

But upstanding law abiding organizations trying to do their best to comply with the laws are punished by trying to make these fuckers happy. It's not worth the trouble.

In the case of vaping, black market/street vapes have no regulation to protect the users. I followed almost every case of "vaping caused x respiratory problem for this person", and in every instance that I could track beyond the initial report, it was discovered that the individuals were buying their shit from illegal operations, who put God knows what additives into the shit they sell, and frequently, if I could get enough information on it, the result was that some bullshit illegal additive caused the problem, not the legit ingredients that are supposed to be in a vape, as governed by law. Those additives have no place being inhaled, and for good reason, they damage your lungs. But mass media's one-and-done style of reporting, never, ever, fucking follows up and the public who don't bother doing any goddamned research of their own start to think all vaping products are bad because reasons.

To bring it back on point. Sites like porn hub, have benign ads. I'm sure we've all experienced the bullshit ads at one point or another that seem to rip you out from where you're browsing and they take over your screen with some crap like "you have a virus, call our (scam) center to fix it".... On legitimate websites (pornhub included) these ads don't exist. If you spend as much time on shady websites as I do, you would know that such browser hijacks still exist. The only thing this law will do is make it extremely difficult to use any legitimate website, pushing people to use less reputable sources for their porn, and leading them right into the waiting arms of scammers and con-artists. This kind of idiotic policy erodes public safety.

IMO, this shit is happening and keeps happening because the law makers are ignorant of how this shit actually works, they don't understand behavioral patterns, and the media reinforces their fears and the fears of their constituents with their one-and-done sensationalist news stories that never get any kind of follow up.