So it isn't a fact that some people are in countries that will imprison them simply for using crypto, or that people are robbed and kidnapped over it, and thus a system of endless inquisition is a threat to some people in this way? No what is important is your semantics and condemnation. You don't argue any of the very logical points I made and instead go for semantics and more accusations. I have brought substance to the table. Now you try.
The bolded part is certainly not a fact. What you call "endless inquisition" doesn't obligate JusticeForYou to do anything, and even if JusticeForYou signed a message - that doesn't create any new dangers for JusticeForYou.
He has already said that he lost his private keys when his HDD died due to an electricity problem in his house. The value of his bitcoin may have been only a few hundred dollars and it would not be out of the realm of normalcy if he didnt have backups.
Signing a 2011 address wont prove anything, nor would signing an address with a hundred coins.
I am not aware of any prior hacked accounts that waited 4 months to start causing trouble they will almost always try to scam or spread malware immediately because of the risk of the owner coming back to claim it.
It is fairly clear to me that the demands for proof of ownership is the result of his criticism of the current status quo.