OpenAI is already very dependent on Microsoft for access to data. And MS is one of their major investors. So there's no pressure on either party to act in a hurry.
A reason for MS to buy OpenAI would presumably be to deny access to third parties to the AI and make it some kind of exclusive MS only feature. The problem with that is of course that all the research has been published already and outside researchers and developers are already replicating their results. That cat is already out of the bag. E.g. Google has some AI models that it has chosen not to release yet that are similar to GPT. Also, companies like this are heavily dependent on their people and they tend to start jumping ship in case of an acquihire where they receive a lot of equity. So, there's a question of what it is they would be buying.
What's more likely, is that OpenAI will power a long tail of smaller AI companies and create a lot of value that way, while the bigger companies will use their data leverage, and access to vast amounts of infrastructure to use the same algorithms to produce better AI models.
MS and OpenAI are of course collaborating pretty deeply with OpenAI already. They are using Azure and have access to a lot of MS controlled training data. Historically, AI algorithms have been public research with the understanding that they are relatively low value without a lot of infrastructure and training data. The likes of wikipedia only get you so far. So, OpenAI is basically that plus MS provided infrastructure and data. You can machine learn all you want on your laptop but you won't get anywhere until you put a few billion on the table for access to infrastructure and data. MS has done that through OpenAI.
I imagine, MS has some pretty favorable licensing agreement with them as well in exchange. That kind of symbiotic relation ship is mutually beneficial. And with OpenAI set to generate some serious revenue in the next years, it's a pretty good investment too.
MS might be better off buying some of the more successful openai using startups in this space and then integrating their features rather than building those features in house. After they acquire those smaller startups at a relatively low price, they can level them up with better data and access to infrastructure. Leave the experimenting and risk taking to the startups. MS has had a relatively successful acquisition strategy in recent years with some real value added to their products via acquisitions.
It's a very different strategy than what Google is doing. Google is being secretive and probably not that effective in terms of generating revenue from what they have done so far (regardless of how good that is). Making search slightly better isn't going to move the needle for them. Google translate is no longer best in class. There are some gimmicky features on docs and gmail but it's not quite at the same level as OpenAI. Typical Google: lots of R&D but very little to show for their money so far.
I think I like the MS strategy better. There's a learning curve with this kind of stuff and doing it in the open speeds that up massively. Shorter feedback loops, more rapid iteration, etc. Google could do the same of course but so far they are choosing to do everything on their own. They are a bit like MS used to be. I don't think that's a good strategy.