Socially-constructed whiteness is a loot-sharing agreement. Ceasing to share breaks the agreement. (Mammonism the cult requires not sharing; if you weren't already rich, God doesn't love you so it's wrong for you to have any money at all.)
The great and good are freaking out because of who the shooter was; it's an abrupt reminder that even if you're rich, the great mass of white men can decide you're not white.
That's a difficult thing to survive even should you become generous with the loot.