The only time a mod account being active matters is when the community isn’t being moderated.

As an example, one of my meat space friends mods two or three communities, and never posts, and hasn’t left a comment in something like a year. But he still checks in daily, despite the communities being low traffic.

On the opposite end, I’m running my mouth all over lemmy daily, but none of the communities I mod have any activity at all because there’s no point to them, which means I never check them any more. So I look like an active mod to some eyes, but he doesn’t. That’s despite neither of us having ever had to take a mod action at all.

If there’s a community already established, and it isn’t active, try posting there for a while and see if it becomes active a lot of people actually scroll all because it’s more interesting on average. So new posts to a dead community can draw eyes, and maybe lead to activity from others.

If that doesn’t work, starting another one is worth the effort.

That being said, sometimes, if the community is on one of the bigger instances, starting the same thing on a smaller one can work out well