People know who Satoshi is or was, in that it's the same Satoshi that invented Bitcoin. (But nobody knows who that is or was "in real life".)

But if an agency has access to that wallet, then any transactions would be visible to everybody. Activity on Satoshi's wallet after all this time would shake up the Bitcoin world pretty hard.

I don't know how sudden activity on this known-inactive wallet would accomplish any of those things.