The only meaningful thing here that makes sense to me is that the “secret sauce” that openAI has is exclusively licensed to Microsoft.

Which means, starting a competing startup means they can’t use it.

Which makes their (potential) competing startup indistinguishable from the (many) other startups in this space competing with OpenAI.

Does Sam really want to be a no-name research head of some obscure Microsoft research division?

I don’t think so.

Can’t really see any other reason for this that makes sense.