I admit I don't get why the absurdly rich - not just superrich, but billionaire rich (not fake billionaire rich) - continue to run or pretend to run companies. Enough is enough at some point, and you don't actually get to take it with you. Seems like running a company makes leisure, or doing good or evil full time, depending on your interests, tough.
As for taking it with you, I had an interesting conversation with an estate planing attorney once. My basic question was why people, to a great degree, wait until they die before giving it all to their already old children. The usual answer is something like "they need something to be able to control their children with." That wasn't his answer. His answer was that, actually, a lot of estate planning is about giving money to the grandkids. They don't really want to give money to their actual children. True or not... interesting!