I think Mastodon is heavily "following" based. I mean you need to find people to follow. I think you can even follow hashtags, which is pretty neat. So lookup if your favorite content creators may have a Mastodon account and follow them. And make sure to enable or disable the "world" view and not just looking at your own feed, if you don't have much yet. Just some random thoughts. If you are already familiar with this, then apology.

As for the Matrix collaboration, I didn't think about this working between Lemmy and Matrix. But it make sense. Because there is also some sort of "bridge" setup you can do between Matrix to Discord. I'm not much familiar with that, just read about it.

All of this is neat. But its biggest strength is also its biggest weakness: Being not centralized. It's kinda like on Linux (and I don't mean the distributions only). I just wish the entire Fediverse would already cooperate. The lack of a centralized place that has all instances and technologies that are based on Fediverse (Mastodon, Lemmy, video platforms and so on) is a huge missed oppurnity.

Even Instagram, a technology not even based on Mastodon or Fediverse, can cooperate with Mastodon. I never used Instagram, so not sure how this looks in reality. But I thought its worth mentioning here.