>there's nothing wrong with leaving things to your kids to run.

where that's true or not, that's not what happened. this is more like "there's nothing wrong with trying to help your son in his career and getting him a job."

Berkshire Hathaway's market cap is a trillion, and Warren Buffet's net worth has never been close to that, i.e. it's not his company so he's not leaving it to his son to run.

You might admire Warren Buffet's acumen and think he'd be good at picking people, but all (for varying values of all) parents believe in their children so it's not easy to tell if you'd be getting his best advice in this case if you were another major shareholder in Berkshire.