I think the simplified question is if OpenAI is a natural monopoly like Google was/is or if that market has a different structure like an oligopoly (e.g. mobile phone market), "perfect" market, etc. On the technological side it seems obvious (does it?) that we can run good models ourselves or in the cloud. What is less clear if there will be a few brands that will offer you a great UX/UI, and the last mile wins.
