From what I have read Bezos always had a minimal role in the technical management of Amazon other than yelling at people to work harder and micro-managing how amazon.com looked. I have not read anything about Ellison but cannot imagine he has been involved in managing Oracle the database vs Oracle the corporation since the late 1980s.
Not to mention Jobs. Ballmer. Some would say Eich (on external politics).
I agree, still the exception, but I feel like it's extremely unfair to say "everyone except" and forget the devil himself :)