Truly a legendary man for finding himself in the right place at the right time.
He's legendary for being Bill's bulldog, and aggressively convincing people to buy Bill's solutions. Whether he was qualified to lead a technical organization like Microsoft on his own, as Bill's successor? Ehhhhh... maybe?
You know that "used car salesman" persona that he had in that internal Windows 1.0 video (https://www.youtube.com/watch?v=DgJS2tQPGKQ)? That's kind of his business strategy -- sell, sell, sell, push, push, push. Don't let potential clients say "no" to Microsoft products. And when you're an aggressive company like Microsoft, you want that in an exec -- but not necessarily a CEO who's in charge of managing the technical developments also. So I think he was really competent and essential to Microsoft's success, even if he didn't make such a good CEO.
(Fun fact: I used to think that the character Palmer from Final Fantasy VII, a member of Shinra Company's executive leadership, was a parody of Steve Ballmer himself based on his name, appearance, and goofy mannerisms. I'm no longer convinced this is the case, but it's a pretty funny coincidence.)
That's honestly a bit dismissive. You might not like him because he's loud and "not an engineer", but you gotta give him credit for tripling their revenue under his watch.