I agree with this, except the "positive PR amongst users" - OpenAI is going to want to extract every single piece of information from users without compensating them a single penny. No way they allow something like permanent deletion of comments. And they will obviously be using every single database entry - public or not, to train their LLMs
Back to the main subject. For me the obvious buyers in terms of makes most sense are Meta -> OpenAI -> Shady data broker. Sam Altman is also one of the investors in Reddit
For Meta it goes beyond the data, which is a plus. There are a ton of similarities between FB groups and Reddit. FB groups is even more popular in terms of DAU, and some communities are bigger there than on Reddit. Plus they also utilize free moderation without any uprisings. Owning both communities would be huge for Meta in generating ad $'s