I've found that the quality of your Fediverse experience relies on your participation to a much larger extent than other social media. Lemmy instances tend to be tech focused and I've found it's difficult to discover new content via accounts there - you don't have the capacity to follow new users, only subscribe to communities.

On the other hand, Kbin, because it reads both Lemmy style and Mastodon style instances, has proven to be exceptionally vibrant when it comes to discovering new content, as it allows you to both subscribe to communities and to users. I've found that once I subscribed to about 100 communities and followed a like number of users, my content feed far exceeds what I get on Reddit - because as the users I follow post to new communities, they appear as posts on my feed.

I think when it comes to non-tech communities, a lot of them suffer from the fragmentation effect of having multiple communities of the same type across instances - because most Fediverse participants are in tech, tech is the theme that unifies the audience. To really match the quantity of content on /r/music, for instance, you'll want to be subscribed to at least 10 communities in the Fediverse. It's also harder to run a community in the Fediverse (although vastly more rewarding), and most mods often end up being the primary posters due to a lack of audience participation.

All that being said, shameless plug for @13thFloor if you're looking for a non-tech community. It's a pirate clearing house of sci-fi, music, fantasy, literature, movies, articles, and all other sorts of weird ass shit designed to engage your imagination.