yes, that's how it works. relays only relay to clients that ask for it, and they can only relay what they have... if you follow someone, you cannot expect that person to write to your set of relays, right? that would be a dumb assumption, so your client is smart and so it knows where your follows post and fetches from there, otherwise you would not see posts you want. why do people expect to find other people's posts on their relays? this comes from a misunderstanding of how nostr works. Also, if you want certain people to read your notes, then you should post to the relays they read their notifications from in addition to your own write relays. This is not rocket science, it's simple logic.