The latter two points about splitting your timeline and muting just reposts is closer to correct, but is not actually anywhere in the protocol as written. #ActivityPubdoes not include these features. They are useful, but they simply do not exist in AP, and to a greater or lesser extent they have either not been formalized or only barely formalized with a #FEP
This is something we can correct and probably should correct, but we also need to stop telling people it is true of the "fediverse."