They would definitely have sales repercussions, but it might be worth it.

They are fully trying to be a consumer product, developer services be damned. But they can’t just get rid of the API because it’s a good incremental source of revenue, and thanks to the Microsoft deal, all that revenue would end up in Azure. Maintaining their API is basically just a way to get a slice of that revenue.

But if they open sourced everything, it might sour the relationship more with Microsoft, who would lose azure revenue and might be willing to part ways. It would also ensure that they compete on consumer product quality not (directly) model quality. At this point, they could basically put any decent model in their app and maintain the user base, they don’t actually need to develop their own.