I wasn't aware that they aren't involved in these events but my guess would be because if someone were to legitimately play in Iron Age they would Age up before the event finished so why bother creating an event level for them. If Iron Age isn't involved in these events, Kudos to the devs for excluding them because that would just be rubbing salt in the wound having a sandbag with a bazooka tower. Not that it stopped alliances from doing it on their classical and medieval bags.