It has a very small community. That is very different from being dead - in fact, that community is probably much more passionate about what makes it specific than a large community.
For example, you'd find that sysadmins are much more prevalent on Gopher than Twitter.
I'd say ratio of sysadmins to actual users of the service is good indication that something is dead
But I do think it is worth pointing out there is nothing wrong with folks doing something to scratch their own itch. It does not have to be hugely popular or have a ton of users. If the sysadmins care enough to keep it running, that it literally all that matters...
I may steal this quote.