The one and only method I will participate in is server operators setting a RTA header [1] for URL's that may contain adult or user-generated or user-contributed content and the clients having the option to detect that header and trigger parental controls if they are enabled by the device owner. That should suffice to protect most small children. Teens will always get around anything anyone implements as they are alr…
For anyone curious about the value, the numbering on the value is just a fixed number everybody decided to use for some reason that isn't clear to me.
I would deeply prefer to do it this way, but my goodness the RTA org needs a serious brush up of their web site and information on how to use this.