Ah ok, I didn't know that.
So my notes are saved and everyone else can see them, but the relay itself cannot be used by others.
Discussion
It could be in theory. People need the address for your relay, it must be reachable from outside (either via Tor or forwarded port) and they need to actively add your relay in their client of choice. Then they will also be querying your relay for posts and pushing their notes to your relay.
ok, thank you!
I'll give it a try! :)