Not as a GSM, no
But I have seen other 3 stripe positions as new hires, i.e., Executive Housekeepers, Associate Hotel Directors, F&B Managers, HR and T&D managers, Bar Managers, Cruise Directors . . . so it's not totally improbable - but . . the candidate would have to have one SERIOUS equivalent background to get up to speed on the demands of the position.
The position right below is the Front Desk Manager, so I'm willing to bet if someone was qualified, they'd start as that first.
Pretty sure Facebook has a RCI "pursers" group where you might be able to ask this question