For example, I’m on Lemmy.sdf.org and I joined the Apple@lemmy.ml community. But there are many missing articles and comments. If I browse directly on Lemmy.ml for the same article there ~90% of comments are missing.
https://lemmy.ml/post/1152794 has 26 comments https://lemmy.sdf.org/post/11232 has 0 comments
This is my understanding as well, after using a number of different instances over the last few months.
I believe this issue will mostly sort itself out in the future as the federated network becomes more “connected”
A new instance connecting to an existing one will have content from the established instance missing, but as time goes on that content becomes a smaller portion of the overall content.
I anticipate some development on this issue in the near future anyway, perhaps cached content that is able to be “pushed” to a requesting instance.
Yeah it’s still definitely an issue considering there will be plenty of old topics that people will want to search and refer back to, and any new instance or people making their own will be SOL if they come in years later after communities have been posting for a while.