I feel the same way. He probably could not have sold a large portion of it without trashing its value, but he surely could have sold a few hundred millions.

And, should the system later implode, he could have easily disassociated himself from this fiasco: "those things would not have happened if I were still running things; I lost a lot of billions; I am a victim of this fiasco, just like you are."

In politics, too, very few leaders manage to leave at the right time: while they are near the peak of success, which looks so much better later on...