People say things like this about Signal but tend not to acknowledge why Signal is like that. Look at how Signal handles something as basic as user profiles, then compare it to how other applications address the same problems. I'll recommend Wire alongside WhatsApp any day, but keep in mind that Wire's servers apparently have a record of every conversation that has occurred between any two Wire users (not the content, mind you, just the link).

This is why I disagree with Matthew Green, do not think we've totally figured out secure messaging yet and that they're all "so good", and think that if you're serious about privacy --- enough to have strong opinions about WhatsApp vs. Signal, for instance --- that you should use multiple messengers:

- a "tier 1" secure messaging app like Signal that makes all reasonable tradeoffs in favor of security and privacy regardless of the UX cost, used when possible and for sensitive conversations.

- a "tier 2" secure messaging app like WhatsApp or Wire as your "daily messenger".

- "tier 3" messenger applications (including email) that you use mostly to rendezvous to a real messenger application.

In this scheme you can start to understand Signal as not just a decent messenger application with best-in-class security and privacy, but also as a laboratory for future privacy enhancements to messaging.