Aren't apps already sandboxed from eachother on both major Phone OS', unlike on Windows? So on that end something like Edges snooping around other browsers isn't even possible.
If the video leaks due to shitty (pun not intended) sandboxing that is rightlfully on Apple (when on iOS), if it leaks due to the browser being broken then it is on Google and if it's due to an explicit modification of Samsung (when talking about Android) it's on Samsung.
When Facebook has a bug/exploit in their app that results in X hacker being able to gain access to files stored within the sandbox of Facebook noone is blaming Apple for Facebooks bug.