I'm not sure I understand what you're saying. Perhaps you could point out where your perspective differs from mine? So, as I see it: Open AI _is_ a non-profit, though it has an LLC it wholly controls that doesn't have non-profit status. It never "became" for-profit (IANAL, but is that even possible? It seems like that should not be possible), the only thing that happened is that the LLC was allowed to collect some "profit" - but that in turn would go to its owners, primarily the non-profit. As far as I'm aware the board in question that went through this purge _was_ the non-profit's board (does the LLC have a board?)
From the non-profit's perspective, it sounds pretty reasonable to self-police and ensure there aren't any rogue parts of the organization that are going off and working at odds with the overall non-profit's formal aims. It's always been weird that the Open-AI LLC seemed to be so commercially focused even when that might conflict with it's sole controller's interests; notably the LLC very explicitly warned investors that the NGO's mission took precedence over profit.