There is a massive amount of tooling and infrastructure involved. You can't just get some Andrew Ng Coursera guy off the street and buy 50,000 H100s at your local Fry's electronics. I wouldn't be surprised if there aren't even enough GPUs in the world for Altman to start a competitor in a reasonable amount of time.
I stand by my number, there are like 4 people in the world capable of building OpenAI. That is, a quality deep learning organization that pushes the state of the art in AI and LLMs.
Maybe you can find ~1,000 people in the world who can build a cheap knock-off that gets you to GPT3 (pre instruct) performance after about two years. But even that is no trivial effort.