First, congratulations on shipping. Usable E2E encryption is something I care deeply about and Signal is the best Ive ever used. Completely agree fighting mass surveillance for avg users is highest priority.
What do you mean by "the velocity of the ecosystem is unlikely to make distributed communication mechanisms possible for some time"?
Ecosystem - tools and services with network effects, like Google Cloud Messaging.
Lots of phone carriers whitelist that server of theirs to allow it to wake up phone unprompted from idle while typically only allowing phone-initiated connection to stay active, and they also tend to block most incoming connections once the phone has been inactive for a while.
While it isn't technically hard to make something distributed, to also make it work well can be troublesome...
Yet another reason I want home servers to become common, as your phone could automatically request that your carrier whitelist your chosen trusted nodes such as your home server.
What do you mean by "the velocity of the ecosystem is unlikely to make distributed communication mechanisms possible for some time"?