For the record, many of the listed business leaders have sold businesses, and considered selling their flagship businesses but felt the offers were too low. I remember reading this specifically about Google, but don't want to find a source (searching "google acquisition" isn't really helpful these days). Jobs sold NeXT; I think he would have sold NeXT even if Apple was not the buyer. etc.
Buffet et al are driven by practicality. Dynastic ambitions are an obstruction on the way to Buffet's status.