Problem is, there's too few people on Lemmy and discovering new communities can be hard. A lot of communities are carried by a few people or sometimes even just a single person. As there is nobody contributing and that one person is basically screaming into the void, communities tend to die.

It's probably better for now to start with fewer, more general communities. Then when there are enough people posting about a certain subject, it can split off to its own community. That way there will always be engagement, even though other people in the community aren't necessarily into that exact topic.

Or another good way would be for an entire community to migrate from for example Reddit to Lemmy. But this can be problematic as the community probably won't agree on where to go to. And there will always be people who aren't as active and miss the migration. Or who don't want to bother and just not migrate. With a tight community it's possible, otherwise it will fracture and maybe even destroy the community.

Lemmy also has an image problem right now. This is partly due to the image problem the fediverse has as a whole (Mastodon has the same issue). But also partly due to the kind of people that are early adopters of Lemmy. A lot of the people who flooded to Lemmy are people who are very tech capable, like stuff to be open and free as much as possible and don't mind putting some work in to get what they want. This is however not how a lot of people are when it comes to using social media. Social media is used to unwind, relax and take your mind off of the day to day stuff. When one of those let's say "normies" ask their local Lemmy enthusiast about an alternative to Reddit to migrate to, the enthusiast is going to tell them about the different servers and apps and how great federation is etc. At this point the normies eyes have glossed over and they aren't going to bother.

I'm sad to say I've seen a lot of communities I'm a part of migrate to Discord. Most people already have a Discord account and have the app installed. They know how to use it and often are already part of communities. Someone creates a community on Discord, posts the link in the old place and everyone can join. For most of them it's just a single click and they can find their regular scheduled content at a different, but familiar place. The reason this makes me sad is because Discord is a commercial walled garden. I'd much rather see more people move to something as open as Lemmy, but I understand why people do it. Finding new communities on Discord is also kinda hard, you have to know someone who's already a part of it, or have a website or something with the link. And we've all seen the backlash people have against a lot of open source communities moving to Discord, it sucks. But it's fast and easy, so that's hard to compete with.