A quick rebuttal of some points you made. Not going too in depth as I just want to provide my perspective:

• CIA Funding:
• • This is a non-issue. The OTF also funds: Briar, Tor, Wireguard, Delta Chat, Bind9, CGIProxy, CertBot, K-9 Mail, Tails, NoScript, QubesOS, The Guardian Project, and a host of other essential privacy tools/software. You’re telling me they’re all compromised just because they’re getting funded? I don’t buy it.
• A Single, Centralized, US-based service
• • The Code is open source and Android has reproducible builds, iOS would have them too, but it’s impossible based on the way Apple’s build process works. Lastly, Signal’s devs/infra exist in the US, they have to exist somewhere, why not the country of origin? With the code being open/reproducible, you don’t have to trust them.
• Phone # Identifiers
• • This is to make onboarding easier and minimize spam - I got my grandma to install it and find the rest of the family on Signal VERY easily. Trying to get her onboard with Matrix/Element or even Briar would have been a struggle. I like Briar, but its not ready for mainstream yet. I also like Element, but I don’t believe it’s quite a text/sms replacement like Signal is - in addition to leaking metadata.
• Social network graphs
• • Here you mention metadata, so I’ll ask which other provider goes to the lengths that Signal does to minimize the collection of metadata? And please read over how Sealed sender works before you claim its easy to circumvent. You deride their implementation and claim how easy this is to collect without understanding what’s going on under the hood.
• Abandonment of Open source
• • This is a stretch. Signal is a non-profit. They don’t have the same funding or staffing as their competitors and all their code is current. Yeah, they let it get out of sync for a while, they’re human, not robots. Don’t let perfect be the enemy of good.
• Bundling a Cryptocurrency
• • What does a messaging platform have to do with crypto/payments? I don’t know, you should ask every other big player who is also trying to get in on the game hoping to siphon even more data from everyone’s purchases.

I do want to close by saying that Signal is definitely not the end-all-be-all of secure messaging platforms, but it is currently the best for mass adoption. I’m keeping my eyes on Matrix, Sessions, and Briar, but can’t say they’re ready to “go mainstream” yet.

Just use Element (Matrix).

Thanks for the nice article!

What it ultimately comes down to is that truly secure systems cannot be based on trust. The article does a good job outlining all the ways the users have to trust Whisper Systems without any ability to do independent external verification regarding what the server is doing with the data available to it.

Even if we assumed that Signal works as advertised the fact that it’s tied to your phone number is incredibly dangerous. Obviously if this information was shared with the government it will disclose your identity as the article notes. This information can then be trivially correlated with all the other information the government has on you and your social network. Given that Signal is advertised as a tool for activists, that means it creates a way to do mass tracking of activists.

Being centralized is another huge problem given that the service could simply be shut down at any time on government order. If you’re at a protest and rely on Signal it could just stop working.

edit: as people have pointed out, it turns out you can use third party clients

Finally, since the client is a binary distributed by Whisper, it’s not possible to verify that the client and server use the published protocol independently. Since alternative clients aren’t allowed to connect to the server, we can’t test the protocol and have to rely on trust.

matrix, jitsi, etc, are very different types if platform from signal. if you just want signal but without all the problems, it’s Wire.

but if you want my opinion - the only thing that matters is bridging. none of these small networks can succeed unless they can bridge to the others and to email. bridging is subverting the network effect to combine the small players and help them destroy the big players.