Now this is a completely whacky theory, but time wise things do make sense.
The Silk Road was launched by Ross Ulbricht in February 2011 and was the driving force behind adoption of Bitcoin as a currency.
He has a lot of knowledge of how the Bitcoin Blockchain worked and how to implement a system which required quite intricate work in 2011 to run the marketplace on the TOR (hidden services) network.
April 23rd 2011 - Satoshi Nakamoto's last email stated that he had moved on to other things and that Bitcoin is in good hands to software developer Mike Hearn. 2 Months after the launch of the Silk Road.
This would be an excellent reason to want to remain anonymous, and also to disappear.
Ross Ulbricht was arrested in February 2014 and has been jailed ever since - which could be why no BTC has ever moved.
Completely unlikely I know, but a theory I never see spoken about that does have some logic behind it.
Maybe he wasn't working alone - who knows.
