Why they don't use zero knowledge proof? Also question for the USA constitution experts, is this considered a violation of free speech? The article is not clear on this.
replies(8):
Not in principle
See the limits on curse words on TV. Or MPAA ratings for movies.
(IANAL) That demonstrates the opposite: that's a voluntary system with no force of law behind it—the private sector "self-regulating" itself, if you will.
The film rating systems were created under threat of legislation in the first half of the 20th century (so, in lieu of actual legislation). The transformative 1st Amendment rulings of the Warren Court would have made such laws unconstitutional after the 1960's, but the dynamic that created these codes predates that—predates the modern judicial interpretation of the 1st Amendment.
https://en.wikipedia.org/wiki/Hays_Code (history background)
https://en.wikipedia.org/wiki/Motion_Picture_Association_fil... ("The MPA rating system is a voluntary scheme that is not enforced by law")