I suspect a lot of this is survivorship bias.

I suspect if one were to compare a large number of startups to one large company (or even better a portfolio of large companies), the “ruthless founders” will significantly underperform the middle management in large companies even after adjusting for the inherent advantages large companies have.

The only reason the “ruthless founders” look better is because we usually only talk about the successful ones because unsuccessful ones have disappeared.

Middle management is more successful and ruthless founders are less successful than immediate appearances would suggest.