Nobody can buy them without bankrupting themselves many times over, unless the big companies buy them (very unlikely)
Or is OpenAI just going to keep raising and raising more and more?
Is OpenAI even profitable?
If you take this at face-value, they probably aren't profitable (to the tune of a $5 billion loss). I don't like idle speculation, but having actually read this their analysis seems pretty sound. Their numbers on training costs and hosting actually came from an anonymous insider. Impossible to say how reliable this anonymous insider is, but planting false, exaggerated numbers to outwit competitors seems a bit too much like a hare-brained scheme, hence why I opt to go with the numbers. If anything, companies tend to downplay costs when lying.
The one thing that caught me as a little bit crazy was spending $1.5 billion on employees. They have ~1500 employees, so that's $1 million per head. That seems insane, but then again, AI researchers are a valuable commodity these days.
Even if the cost of employees was $0, you'd still be looking at estimated losses in the billions.
There are lots of M&A structures. A company can in fact buy another that is bigger than itself. Plus Microsoft will easily be able to afford a $100B acquisition with some creative financing, or maybe even outright cash.
One aspect of The Singularity is the rapid acceleration into an unpredictable point of no return. Maybe the financial model mirrors this?
One aspect of reality is that governments actually like to govern predictably and those with sufficient military power make sure they can.