Bars and Casinos argued the exact same thing when we mandated they check the IDs of a patron before serving them a drink. The world didn't stop spinning.
It's not really a good point. Yes it's more difficult, but that doesn't exempt them from complying. And they've made basically zero effort to comply.
You could argue quite convincingly that the explosion of adult content sites is due largely to evading regulation and reaching a wider (ie: illegal) audience.
What are you talking about though? I don’t care one way or another whether the porn company makes money, fuck em. The problem is if your law doesn’t prevent kids from watching porn but instead pushes them to shadier sites.