He's not even using double spaces like Satoshi did.
This isn't even remotely reliable as proof or disproof and only muddies the water further.
Stick with digitally signed messages. Nothing else short of this will be sufficient.
I'm operating under vastly different "assumptions".
Satoshi might be anonymous to nearly every common people, but he certainly wasn't anonymous to the government and secret services because they have means at their disposal which common people don't.
This means that secret services can catch him, tell him "cooperate or else" and then take his keys and tell a pretender to play Satoshi with the original Satoshi's keys - while Satoshi is killed or jailed.
I would need either multi-threaded proofs or at least a high level of consistency in Satoshi's behavior.
Single-threaded proofs aren't very reliable for my preference, even "extraordinary proof". Case in point: I once asked a friend of mine... what would it take for you to believe someone is god? Would you believe they are a God if they commanded natural phenomena like the weather - on command? He said yes. I then showed him the sky. I told him to pick any white cloud he liked and point it to me. He told me ok, that's the one. Alright I said, wait a bit. 80-90 seconds later he was like "W T F, how are you doing this" (the cloud was dissolving). I told him "well, obviously I'm god...". Next day, and after I had explained to him the mechanism, he's like "oh it's easy, I was dissolving clouds all morning". So what was enough to declare me a "god" a day prior, the next day was "easily done by anyone". So even the benchmark of "extraordinary proof" can be bullshit, under circumstances.
Just because someone has Satoshi's keys, or coins, doesn't make them Satoshi. Not that I have seen such a thing though.