Platform economics "works" in theory only upto a point. Its super inefficient if you zoom out and look not at system level but ecosystem level. It hasn't lasted long enough to hit failure cases. Just wait a few years.
As to openai, given deepseek and the fact lot of use cases dont even need real time inference its not obvious this story will end well.
I also can't see it ending well for OpenAI. This seems like it's going to be a commodity market with a race to the bottom on pricing. I read that NVIDIA has a roughly 1000% (10x) profit margin on H100's, which means that someone like Google making their own TPUs has a massive cost advantage.
Moore's law seems to be against them too... hardware getting more powerful, small models getting more powerful... Not at all obvious that companies will need to rely on cloud models vs running locally (licencing models from whoever wants that market). Also, a lot of corporate use probably isn't that time critical, and can afford to run slower and cheaper.
Of course the US government could choose to wreck free-market economics by mandating powerful models to be run in "secure" cloud environments, but unless other countries did same that might put US at competitive price disadvantage.