The problem is discoverability. You don't know where to look for stuff or people. I wanted to check out this whole Lemmy thing and found almost completely dead (no comments) communities linked from their project page.
Where do I go? How do I search for something worthwhile? There's no central space to find it, compare communities etc. I was curious but now I am kind of put off.
It just needs to be posted as a main aggregator at https://join-lemmy.org, or even better, on the right hand side panel on every Lemmy instance.
I know this would be a centralized database of communities (which is probably frowned upon in the fediverse) but I don't think there's a sensible way around it.
Discoverability is a double edged sword. You'll find it, but so will every bot and scammer on the planet too. Then moderation will get ever stricter to get rid of the abusers and eventually the place becomes a mess for one reason or another.
I'm sure spam bots and scammers aren't waiting on indexes to appear and do their own, so providing an index can't make them more problematic they already are.
Trolls, bullies and harassers though will have better access to you.
I ran into this same issue. But I asked myself, if I passed through and left because no one was active, why not plant some seed content for the next person that passes through? I couldn't be the only one looking for smaller, more intimate communities.
I did this for a "dead" forum and after about a week of "squatting" there and posting for myself, other people started showing up and replying to it.
People should treat the digital silence of dead communities as an asset and free real estate to share their thoughts.
I checked and you can find a good number of communities by going to one of the larger Lemmy sites, clicking on the Communities tab and selecting All. If you want one directory from many instances (I assume this is what you meant by central space), someone would have to create it.
Where do I go? How do I search for something worthwhile? There's no central space to find it, compare communities etc. I was curious but now I am kind of put off.