So, while a given community is overseen from a host instance, the actual content you're reading isn't. By subscribing to a community, the content there gets delivered to the instance you're on, creating a local mirror.

On Mastodon and the other microblogging platforms, this subscription is done on the user level. If one person on your instance subscribes to a user on another instance, that users' posts are available to everyone on your local site. Here? I'm not totally sure at what level content gets shunted and shared around.

But it's definitely not centralized. You're not reading posts on other websites. You're just reading posts from other websites.

Fracturing the conversation also isn't a super bad thing. From my end, I subscribe to many of the same type of topic across multiple instances, and it's seamless to me for reading and replying. If one instance suddenly went away I'm sure users would quickly migrate to one of the duplicates.

It's not like reddit is any better about fracturing. There's two different San Diego subreddits because the mods hate each other. There are plenty of other examples but they are rarely talked about.

What would be the best way to search across lemmy instances. When searching through duckduckgo, I often add "site:reddit.com" because the otherwise the search results are garbage. But using a domain name wouldn't work with lemmy since each instance has it's own domain.