Earlier quoted context omitted.
"The people who use Snapchat have a threat model that includes the ordinary people around them: parents, friends, friends of friends, etc" Who were downloading apps that could keep Snapchat pics at the time Snapchat users were telling me they went away and nobody could retrieve them. The Snapchat company could also sell them to the same people. That means, due to no attempts to learn about online privacy, they falsel…
Making sure nobody can screenshot a snap or save it is an entirely client side programming problem, it's got nothing to do with cryptography, so all the other 'easy to use, private solutions' wouldn't be any different in that respect.
Our point is it's a lie to even tell users that if it's so easy to beat it. Stronger privacy would require a DRMed endpoint where it was a real pain to get those screenshots. Stronger privacy than that is not using the app at all or for anything private. That it's a company whose business is likely to sell out their users is the biggest reason why they don't really get it. Apathy to learning about these fundamental things is what lets such companies get them with false promises.