It wouldn't be insane to say that Microsoft could have bought Sony, or that it happened the other way around either.
Bro, that would be insane (Sony purchasing Microsoft). Microsoft is too large of a company spread out into many different industry sectors.
It would make more sense to have Sony only purchasing Microsoft's game division rather than Microsoft as a whole. Personally, I wouldn't mind it. Microsoft and Sony produce gaming consoles that aren't too different from each other with the exception of a few console exclusives such as Halo and God of War.
Anyways, I doubt this means anything but some speculation doesn't hurt.
Edit: And it turns out this doesn't mean anything.