I get the whole “lemmy is a lot of independent servers, which can communicate to each other”. But i dont really understand why i cant see All the post or comments in a sub.

For example: I createt my acc in lemm.ee and subscribed to chainsawman@feddit.de. Now i can see some posts but not all of them (like i cant the the pinned post) , i cant see comments, i cant see the Real subsciber-count aaaand i cant see a post i created on the sub (not even in my profile).

Is this all because of how the apps work? Because it seems to work, when in enter the sub directly via my browser.