Presuming the Eastern liturgical rites avoided updating, that would be one thing.
However, all the Eastern bishops accepted Vatican II, so whatever they retained liturgically has been undercut by what they have accepted doctrinally from the council.
Not everyone who “accepts” V2 believes in its errors. V2 is ambiguous, and many interpret it according to an orthodox meaning. Even Archbishop Lefebvre and Bp. De Castro signed the docuмents.
The pastor or eastern Catholic Church I attend is doctrinally sound. Some eastern bishops and priests are heretics, but many are not,