World was already the biggest by far when I first started lurking back in July, and it’s just getting more dominant. Before, there was quite some diversity in the distribution of generic communities, but nowadays the vast majority of posts that reach the top are from over there.
I really can’t see any specific virtue that it has; uptime is not the best (or so I’ve heard), the moderation is quite lacking (which is demonstrated by the fact that Beehaw defederated them), they make some unpopular moderation choices (like blocking !piracy@lemmy.dbzer0.com), and overall the atmosphere is a lot less… nice than those of smaller instances.
I also feel like it goes against the idea of the Fediverse that one instance has control over most of the platform. Especially on Lemmy, where communities mean that building community within an instance makes so much more sense than elsewhere, and upvotes are federated near perfectly regardless the size of your instance, decentralisation makes a lot of sense. It really just doesn’t make sense to me that Lemmy World is where people are going.
Remote access of other communities is a smoldering mess. You have to hope the community you want to subscribe to shows up in All or you have to know its name and use the search feature. There’s no way to see another instance’s communities, unless you have an account there, which is a huge problem because you have to go through the huge hassle of signing up for an instance just so you can find the community, and oh yeah, most instances aren’t even open to invitation so it’s not even possible in a lot of cases.
Also if you get banned from a community it force-unsubscribes you, and if you get banned from an instance it won’t even tell you.