Essentially. Their notes (and other stuff) are filtered out at the client level.
Discussion
If you block/mute on one client does it carry over to other clients.
I think the answers probably no, unless there’s something else going on? 🤷🏻♂️
Event Kind 44 covers mutes, but I'm not completely clear on how mute/block lists are stored.
https://github.com/nostr-protocol/nips/blob/master/28.md#kind-44-mute-user