The core issue is that bridge assistants' requirements are still generic and inaccurate. When I think of a bridge crewman I think of an experienced contractor who flies a medium-sized ship, is in charge of the Bridge if/when senior Command personnel is not present, handles the announcements, flies the other shuttles, leads expeditions and are more-or-less responsible of the day-to-day activities of the ship. Not to mention, they're all armed.
In my opinion, the 30 years requirement is alright, as they're meant to have considerable responsibilities and training to back it up. It can be further justified by giving them extra requirements like a bachelor's degree and at least three years (or more) of experience as an airline/commercial/military cruiser pilot.