That's true, but not a bad thing. We reward charitable donations for a good reason. Ideally, he'd have given away his fortune as he made it (and lived in a world where that wasn't risky), but we live in a world where it seems responsible to save millions or billions and grow them, then dedicate it something as you realize you can't take it with you.
The Koch Family Foundation for Fossil-Free Energy would go a long way.