What do you think these other things could be?
I generally assume he was moving on to battle an illness, and that he lost the battle and died.
Probably this. He was dealing with ALS, and he died. He was probably Hal Finney.
We like putting negativity in something, the fact that satoshi said he was moving on does not specifically mean that he was passing on, he never said he was passing on, the English is clear, maybe after releasing this, it could even be a prototype of the main thing which he has seen that it is getting response, he could be moving on to other bigger projects which may also shock us in the future.
I so much believe that this satoshi hiding is face is purely a deliberate action, and he must surely come out one day the moment he sees what exactly he wants bitcoin to achieve. If he is not a super human being that was sent from the future, I know surely within me that satoshi is even watching many things we are doing, and maybe still even investing too to test things around.