Signal is a stunning success. If you or anyone does better I will cheer and yell about your success often.
>We now know there were zero-click iMessage exploits being used by oppressive governments to target politicians, journalists and activists.
Firstly citation needed please. Secondly, great, should they have been using email and pgp? Or google chat? Or are you saying the NSA should have just had all comms on their servers without going to any further and targeted effort.
Any software project can be criticised. And _should_ be. Just when you do it don't overlook its success which for signal was the first one that actually worked after decades of efforts. Now go do better.