Because, IIRC, when a charity nonprofit like OpenAI, Inc.-- a 501(c)(3), other nonprofits are different -- converts to a for-profit (C-corp or otherwise doesn't matter), all the assets acquired while it was a charity must either remain dedicated to and used exclusively for the charitable purpose, be returned, or be donated to charity (or sold, and then the proceeds treated the same way.) For the charity OpenAI, Inc., this would include its interest in OpenAI, LLC (the wholly owned subsidiary through which it exercises control of OpenAI, LP and OpenAI Global, LLC -- the latter being the for profit entity that actually sells product, etc.), and OpenAI, LP (the holding company which in turn is majority owner of OpenAI Global, LLC).