I don't understand at all how technical details of the internet should be guideline for the limits that the law imposes on online platforms.
If there is a social norm and already laws that prohibit say, pornography being available to children, on every medium, then internet platforms shouldn't get a free pass simply because they're internet platforms. (opinions on the particular issue aside for a minute).
I'm a little tired of somehow having to accept that internet giants can do what they want and deserve a special role in society because they're internet companies, and every critic is brushed off with personal attacks.