Why are communities on Lemmy.ml more full compared to the same on a different Lemmy instance? - SDF Chatter

For example, I’m on Lemmy.sdf.org [http://Lemmy.sdf.org] and I joined the [email protected] [[email protected]] community. But there are many missing articles and comments. If I browse directly on Lemmy.ml [http://Lemmy.ml] for the same article there ~90% of comments are missing. https://lemmy.ml/post/1152794 [https://lemmy.ml/post/1152794] has 26 comments https://lemmy.sdf.org/post/11232 [https://lemmy.sdf.org/post/11232] has 0 comments