I respect the man for his positive and pro-Bitcoin stances, but I think Michael Saylor is exaggerating here, I don't know if he is being honest or if he has other goals, but it is clear that this is a fantasy far from reality.
There are many rich people who donate a lot of their money to the poor, but I do not expect any of them to donate all their wealth to the poor, if Saylor is as he says "I am a single man, I have no children" then he may donate all his wealth after his death, if he does that it will be a great humanitarian act that will raise the status of Bitcoin.
If he is honest in his words, he can write his will from now because no one knows the time of his death.