Browsing Local vs Subscribed
Why would I want to browse Lemmy "Local" instead of subscribed? It seems that "Local" can serve up just about anything, including things that have nothing to do with the types of communities that I have subscribed to. If I understand correctly, "Local" shows any post to any community on Lemmy.world, which could be just about anything. So, maybe I am missing the point because I don't really see why anyone would want that.
The same reason why you might browse r/all or r/popular on Reddit. If there’s nothing new on your subscription page, you can carry on doom scrolling on local.
Discovery, and instance specific content, where the instance is topic focused
Why not both? Local and Federated are useful for discovery, an unfiltered (and unalgorithmed) look at the world. If that’s not your thing, stick with Subscribed.
What’s in local depends on your instance. It’s pretty good on mine because it’ll give me stuff that’s relevant but not top tier interest.