Of course the cost isn’t near zero, but is the pricing “at Microsoft’s cost”? If it is, then them building a datacenter wouldn’t save anything, plus would have enormous expenses related to, well, building, maintaining, and continuously upgrading data centers.

Good point. I updated the assumption accordingly. I assume the cost of using Azure cloud after discount but before the credit will be on par with Azure's big customers. And given the scale of OAI, I suspect that the only way to be profitable is to have their own infra.

Wouldn't it be foolish for microsoft to give them a discount?

Like you could discount say a 10B investment down to 6B or w/e the actual costs are but now your share of OpenAI is based on 6B. Seems better to me to give OpenAI a "10B" investment that internally only costs 6B so your share of OpenAI is based on 10B.

Plus OpenAI probably likes the 10B investment more as it raises their market cap.

The cost of vertically integrated inference isn’t zero either.