their hobbies or interests.
What are your hobbies or interests? There is probably a community that could use more discussion indeed. I usually recommend moderators of niche communities to set up a weekly thread so that people can discuss things. The best is to have a few users posting daily, but that’s harder to find the most niche the community is (hence why focusing on more generic communities probably makes sense with the current userbase)
Maybe you can start discussions yourself? A generic “how is everyone doing with our hobby”?