Your comment is close to hitting the weak point: you have to trust Apple. If you can’t, then this single / multiple devices detail doesn’t matter: they could fi

Your comment is close to hitting the weak point: you have to trust Apple. If you can’t, then this single / multiple devices detail doesn’t matter: they could find a million ways to silently subvert the encryption in a closed source app on a closed source OS. But if you can, then waxing on details doesn’t matter either: you trust them, so you trust them. The thing is: it is valid to trust a company to keep their explicit word. That’s a different issue from trusting a company who never explicitly said they wouldn’t listen to your data: companies can be held liable for these sorts of public statements. If Facebook silently (knowingly) subverts Whatsapp E2E, they’re in trouble. But reading regular Facebook messages for ads? Storing them plain text? They never said they wouldn’t. This is why Apple explicitly stating they E2E iMessage is a data point with value. It is valid to trust Apple more now, simply because they’ve upped the stakes for themselves. Compare this to a bar bet: someone makes a claim, I am sceptical. They say, honest! Still sceptical. They say ok, bet you £300. I suddenly am much more inclined to believe them. No money changed hands :)