oh my fridging gawd, i am so triggered by this. the site linked to is supposed to advertise a book on ux with some example content and yet literally every comment here is suggesting a way to improve on the UX of that with some even just downright reformatting the content as a comment.
i hope they don't sell a single book as this serves as an example of how to not do UX.
algorithms don't matter for shit to the person that controls the (mandatory) updates.
its the same issue with all modern e2e apps like whatsapp or signal, if there is a single client implementation its not secure at all to these kind of attacks.