Like there's a review on the Android Signal app complaining that it asks for too many permissions, and it does ask for an arm, a leg and your soul, with the reply being unprofessional imho. I understand that this is open-source, but if you publish it and want users, you need to act professional, otherwise it shouldn't be a surprise when people complain.
To the subject at hand, I strongly disagree.
Moxie says that email is frozen, being why it is unencrypted, blaming the lack of progress on it being federated. But you know, I'm willing to bet that in 10 years from now WhatsApp and Slack will be both dead, just like Yahoo Messenger and ICQ before them, while email and IRC will still be around.
And I think that email is unbeatable, because it is federated, because it's governed by standards and because in spite of all constraints, it's quite adaptable, being the kind of platform supporting short term proprietary solutions because (and not in spite of) its client/server decoupling.
Slack for us is just a long and one dimensional stream of greetings, jokes, warnings and meaningless blabbering. Email on the other hand is the archive of everything we do, being the Git of our interactions and the primary channel for knowledge dissemination.
Is it unencrypted? Sure, but it doesn't matter though. Because we are willingly trading that for a capable search engine and a good web interface. Trade secrets aren't communicated over email anyway.
I think Moxie is missing the point. He's emulating WhatsApp, but you can't beat WhatsApp at their own game. Did WhatsApp really deliver encryption to 1 billion users? Well, those are 1 billion users that probably won't use Signal or chat with Signal users. Oops.