I always got the impression the zone was simply rarely used. People could start in EITHER Atlas or Galaxy and the huge majority were in Atlas. Teams forming where the crowds were. Plus the SGs recruiting, tended to favor Atlas. With the Galaxy zone virtually empty by comparison, I would guess they would want to retire it. To make a zone absent, destruction was the only way...
I do remember our group on Virtue, Golden Age Heroes always doing events in the Galaxy arena. Big band and Swing music on the Cape Radio, with themed costume contests. A lot of OLD 40s and 50s era costumes were common. We even had one event where the RIKTI raided the zone mid event.