Lemmy needs a middle logical layer to really take off. If a local server moderats it as such, the default view for say /c/technology shouldn't be slit across a dozen instances. Instead it should be merged into one view.
Without it you have a bunch of largely stagnant communities.
What would be better is if similar Lemmy communities could, by mutual agreement, "federate" so that all posts show up regardless of which community someone is viewing. So if you were looking at lemmy.world/c/technology, you'd also see posts lemmy.ml/c/technology if they "federated" (probably a better term to use to avoid confusion with the fediverse in general, but that's the one that came to mind).
It might be a good feature/option of a frontend to automatically aggregate same-name communities across federated servers. Bogus actors would either be downvoted or defederated off the feed.
Lemmy pretty much just needs tags. Like you can mark your different "technology" communities with the tag "technology" and a user can subscribe to this tag to view all posts from whatever communities have this tag (and they don't have to call themselves strictly just "technology")
Something like that I would imagine so no direct interaction between communities required.