> I don't understand "ruse" here. Protecting children wasn't a serious motivation of many people who supported it?

Maybe the ruse is using the motivation of protecting the children to downplay the First Amendment issues. At least some of the legislators might be so sincere and serious about protecting children that they don't fathom how broad the First Amendment's prohibitions on content-based regulation are. Or maybe the ruse is that the legislators frame the act as a design-based restriction or a conduct-based restriction rather than the content-based restriction it really is. In First Amendment cases, the strict scrutiny test applies to laws which indirectly cause removal of legal speech, not just laws which directly require removal.