Pieter Wuille may be one of the many candidates for Satoshi Nakamoto but you need to provide more proofs for your hypothesis if you want to prove he is really Satoshi.
You need to compare writing styles and other things, not just 4 days registration difference between Satoshi and Pieter Wuille, that proves nothing.
One thing is sure about Satoshi identity - he is not Craig Wright aka Faketoshi, anyone else is possible candidate including Pieter Wuille.