Well looks like our government (I'm French) is having the NIH syndrome as well. Why not reusing existing solutions like XMPP + OMEMO? They can invest a few thousands euros in those projects and in a couple of open source clients. Plus this will also allow the citizen to have a nice, government funded, encrypted solution.
But hey, it's not "sexy" enough. So they'll drop some public money to a big company that knows "what they are doing" and deliver a crappy platform that no one will use :) It already happened too many times.
Because it's not about building an encrypted solution, it's about building "our" encryption solution, so that we can break it when needed and infringe on privacy of citizens. Western European countries are going full speed ahead on censorship and surveillance, so no wonder they are trying to fight 'pesky' foreign encryption schemes.
XMPP is legacy, and rightfully so. With it, by default, communication is in cleartext, there is no way to ensure message reliability and integrity without privacy implications, and multi-device support is arkward.
But hey, it's not "sexy" enough. So they'll drop some public money to a big company that knows "what they are doing" and deliver a crappy platform that no one will use :) It already happened too many times.