I think it was just an excuse so that we wouldn't bother searching for Satoshi or the person behind the name.
What if Satoshi is still around and hiding with another pseudonym ?
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.
And this could also be true and could be the reason why Satoshi couldn't comeback to the community.
It has been 10 years now many things could happen maybe before Satoshi even begin creating Bitcoin the person is already sick.
We can't change the fact that it was possible right? but let's just stay optimistic because we can't easily say those things particularly now that Satoshi's identity is still hidden. Also, he/they are the only one who can tell the meaning behind those messages. You have your point there and its absolutely true there are possible things that happened in those years, maybe he's sick or maybe its not about his/their health well I just admire him and his decision because there can be a lot of reason why he have said it. I'll accept it and just be grateful for what he have done for us.