Users I’ve muted with other clients still show up got me on Primal sometimes. I don’t understand why, but that is happening.
Discussion
My guess is the caching.
There are also private and public mute lists. Some clients use one, or the other, or both.
Imagine a personalized WoT relay that decides what goes on your feed, trending lists, recommended follows, etc, and the client fetches that from your personal relay. Which means that if you want mute to mean mute, then it does bc you control your relay.