The problem is that signing up on one instance locks you to that instance. If the instance goes down, so does all of your data, history, settings, etc. Sure, you can create multiple accounts, but then it's up to you to create secure, unique passwords for each and manage syncing between them. Nobody will do this for more than two instances.
Without this, people will be less willing to sign up for instances that they perceive "might not make it", and flock for the biggest ones, thus removing the benefits of federation.
This is especially bad for moderators. Currently, external communities that exist locally on defederated instances cannot be moderated by the home-instance accounts. This isn't a problem of moderation tooling, but it can be (mostly*) solved by having a single identity that can be used on any instance.
*Banning the account could create the same issue.
Communities need to federate too.
Just as instances can share their posts in one page, communities should be able to federate with other, similar communities. This would help to solve the problem of fragmentation and better unify the instances.
Obviously there are plenty of bugs and QoL features that could dramatically improve the usage of Lemmy, but these two things are critical to unification across decentralized services.
What do you think?
EDIT: There's been a lot (much more than I expected) of good discussion here, so thank you all for providing your opinions.
It was pointed out that there are github issues #1 and #2 addressing these points already, so I wanted to put that in the main post.
@DaughterOfMars That’s why you do your research and create an account on a successful instance so you don’t have that problem. I have a lemmy account and mastodon. I have lemmy because of the blackout but didn’t know what I was doing. I note know how to use lemmy and mastodon from the user side of things. Lemmy for my subs and general looking at the sub home page and communities. Mastodon to chitchat and everything else
You're pointing out the exact problem that I am describing: Users will naturally flock to the largest, most stable instances, thus centralizing lemmy and removing the benefit of federation.
@DaughterOfMars True that. I did my own research and now know what the fediverse is about and wish I didn’t jus blindly follow people. I could have joined an instance of what I liked. Oh well lesson learned. There needs to be a faq about the fediverse before people just come.
Except not when Instances pop up for very specific niche categories. The owners can decide how to run them. Since they will likely be impassioned subject matter experts. That will spread the load of moderation away from general instances. Then if their owners get shady or whatever, someone else can create their own and they can post on the big general instances about their new hockey ballet Fortnite instance and the old instance owner can't stop them.
Mastodon/lemmy interaction needs to get better, yes, being generally text-based I think they should pretty much merge, protocol-wise. I also want to be able to subscribe to peertube channels though wouldn't even begin to expect my instance to suddenly provide video hosting.