If you were in his shoes, can you declare your crypto asset to your family? Or do you think he should have declared it to them after the extended family members must have left and even if he did, the information can still leak to the extended family and from there it can escalate to other people. What opinion do you have to give in this situation?
His crypto assets should be his personal wealth that he can chose not to share with anyone since no one can be trusted, and in this wicked world we are leaving now, anything can happen because many people can betray you and set you up especially if they see how huge your investment worth which is very dangerous.
He can even tell them the worth if they insist, but he should never share his key with anyone because he can’t trust anyone since they are all against him leaving his private life with his wealth.
Truly anything can happen if one makes the mistake of sharing or declaring their crypto assets carelessly. I believe from the story, that he never made such a mistake of doing such because that might just be the end for him as he would not have been safe if he had done such. Looking at it this way, his siblings did not declare their assets so why should they want him to do such putting his life at risk? what if he does that and they discover that he is wealthier than them, do you not think it would raise jealousy in the family amongst siblings which would result in something else if they are not that united and cooperative?
His right to keep his asset to himself is his fundamental right which he owes nobody any explanations, it is his own personal wealth and nobody should have intefered into it by telling him to declare it in the presence of their extended family.