Some of the gear was intended for AQ, while other items may have been back burner or may have been a form of catch up gear.
Think of our tier gear, they got modified and increased in power several times, many other items saw drastic improvements in performance for the sake of a catch up mechanic.
If those items are not included til Phase 6 Naxramas that’s ok, because it was that way originally. Remember the content in this game is easy yet fun we really can get by with out it =)