Makes me curious... how does a hacker this dumb even manage to get access to Satoshi's email address in the first place?
I wondered that myself. The only theory I have that some organization has access to a gmx.com as a whole, and is just provoking to get some reaction or more information.
In some countries, gmx is not working properly since more than a week. Gmx IS crappy, but it has never been this bad in the past couple of years. So yes, I agree that it could be possible that a bigger organisation could be behind it - organisation in the meaning of "computing power", not "brain power", i.e. some hackers who have some technical resources.
On the other hand: The way the hacker(s) act is plain dumb. What kind of reactions could they wait for? Maybe they tried several things in the past and everything failed. So they try to cash out now.
I remember about a year ago, there were some hackers in a forum claiming that they found a way to compromise the official wallet for mining to their address. If they were the same, and they didn't succeed, they may be at a point now where they see that the account is useless and the only way to cash out is to "sell" the "identity".
Nothing of what was posted until now convinces me that they have SN's identity.