When you say a fandom is dead, it’s a bit of a blow to people who are still producing and enjoying work for that fandom. You’re basically saying what they’re doing doesn’t matter, doesn’t count, which might discourage them from continuing to participate.
If one person is creating content, the fandom isn’t dead.
If one person is consuming content, the fandom isn’t dead.
If two friends are chatting on skype about their OTPs, that’s fandom.
If someone doodles drawings of their favorite characters on a napkin, that’s fandom.
Just because someone is producing content for one fandom doesn’t mean they have to leave another.
Not every fandom can be the big, new, shiny and popular thing.
Not every fandom *should* be the big, new, shiny, and popular thing.
It’s okay to have small, tight-knit fandoms. They can be just as fulfilling and entertaining as the big ones.