Instead of rambling on and on about "end to end encryption" or "double-ratchet cryptographic algorithms" or other junk only nerds care about, approach it like this:
* There are no ads, and none of the messages you send can be used for advertising
* It's not owned by Facebook, Google, Microsoft, or any of the other mega-corporations, and you don't need an account on one of their sites to use it
* It will still work great if you travel, change providers, etc
* It's much safer to use on public Wi-Fi than other services or SMS
Honestly, don't even touch on law enforcement access as in the OP. That can strike a nerve for some people. The best appeals are the simple ones.
I think the common mistake is trying to convince people with the security. Use that as a bonus, not the main feature. You're talking geek to people that don't speak geek (convince geeks with these arguments, not mom and dad). I also suggest strong arming people and using momentum (if 4 people in a group of 5 have Signal, switch the group to Signal. Or respond to WA messages on Signal).
As far as I can tell, nothing really happened afterwards. I use Signal on a daily basis and haven't noticed any coin-related functionalities. Either they were canceled, haven't been released yet or they're just buried somewhere deep and not advertised.
Do you have a different experience?
It's still a pain to buy MOB in the US so it's not that usable in the states. It would have been interesting to me if they just used Zcash instead of rolling their own, but I'm not sure what's supposed to be special about MOB vs. Zcash.
I also don't think it's that big of a deal.
https://support.signal.org/hc/en-us/articles/360057625692-In...
The day facebook went down for some hours I got phone calls.
But most of my American friends that don't have international contacts still just use SMS because they are not really accustomed to an app such as WhatsApp and so on.