We wouldn't know for sure if Satoshi did. They were both nyms. But it's definitely plausible. https://image.nostr.build/49dd5ccf9c9c1cd84f7361ca494b9121671de08fac993f56c2852045a4bb0cb3.png
Likelihood of a common identity can probably be ascertained through stylometry & other methods of behavioral analysis— I'd be surprised if it hasn't been done already, to be frank
Plausible for sure.