Comment by ttul

If Apple does start enforcing signed attestations, they will say that it's to reduce abuse. I have no doubt (being in the anti-abuse world) that spammers and phishing gangs will immediately begin using Beeper to spam iMessage users because this allows them to avoid buying an iOS device. With end-to-end encryption, Apple may also decide to roll out privacy-protecting client-side spam and phishing detection, which would IMHO be a really great thing.