I had forgotten that OpenAI started as a non-profit. Elon Musk gave $100 million for a non-profit cause, and even he doesn't know how OpenAI became a for-profit company. I am not sure about the legality, but this transition seems like a unethical rug pull against the early contributors.
non-profits can own for-profit businesses. They generally invest their endowments in...the stock market, and owning a whole company is just that at a larger scale.
A well known example is Usenix taking its networking sideline and turned it into the company UUnet which let Rick Adams become a billionaire (for a while). I actually considered this scandalous and still do, but it was all legally above board. It ended up ensnarled in the Worldcom fraud, which felt like poetic justice to me.
He fundamentally misunderstands what it means to be "non-profit" (or is being intentionally disingenous; it's hard to tell with him). It doesn't mean you can't make a profit.
https://twitter.com/elonmusk/status/1636047019893481474