It’s more like running a PaaS product backed by AWS and then your customers realizing they can just use AWS directly, pay less, and have less complexity. And they have done this before for what it’s worth.
The assumption behind why you'd use the program is that you have access to a proprietary dataset of sufficient size to build a large model around (say, for example, call center transcripts). This almost certainly means OpenAI doesn't have access to train their other models off that data, and it almost certainly means your customers can't take the same data and go straight to OpenAI.
I'm assuming that the target customer of this is people whose moat is proprietary data. If their moat is a unique approach to building a model, then it would indeed be dangerous to engage OpenAI. But then I'd think OpenAI would be hesistent to engage as well.