Maybe he simply lost access to this address ? This is something rather common, sadly. And thus he might have said the truth when he said he sold all his coins.
Why would he? One of the most renown developers of bitcoin has lost access to his wallet?
In 2009 when he received some worthless tokens in extremely early development (as a simple test), he could easily have lost access to his wallet. It's not particularly unlikely.
"I no longer have the keys that were referenced in my initial emails with Satoshi. That's why the remaining coins are unspent. At the time bitcoins had no value at all and nobody else was using the system, so I didn't bother backing up the wallet and eventually lost it."
Hang on a second, so this is what you're doing:
-Insulting people for believing Mike when he said he has no coins left
-Believing Mike when he said he has no coins left