As opposed to Steve Jobs, who was not an MBA, but a dreamer. But with money. Nothing is going to upset the apple cart (pun intended) as fast as a dreamer with money, and the success of the Apple 2 made it possible. They nearly lost it all , too, with the Lisa.. but that experience and UI design went to good use with the Mac.
As far as John Sculley.. ("d'ya want to make sugar water all the rest of your life?") Steve did admit "what can I say, I made a mistake"..but despite Sculley's disastrous leadership, IMHO, no, had he not gotten turfed we'd have had no "Next", therefore no OSX, and no post 1998 Apple rebound. And had he not returned, we'd probably had the return of Jean Luis Gassee, one of the the Sculley era Apple contemporaries (He was CEO of Apple France) who, along with Spindler, were mainly responsible for Apple's slide into the bargain bins of the department stores. And, not content with nearly running BeOS into the ground, he would have returned to Apple and done the same thing to it. I'm not saying that the Be OS wouldn't have been a wonderful basis for the new Apple Operating system. For several years I was a diehard devotee of Be (well, less than 2 years, actually, as it died hard and suddenly) With BeOS underpinnings, however, there's no question MacOS would have retained the "friendly" aura it always had with the classic desktop, and in all probability would even look the same, and even run the same apps but with more stability.. kind of like what A/UX promised but never really delivered. Actually, it makes me now wonder if Haiku has reached the practical daily user stage for an OS. Naw.. probably still not... Now if it can go a couple of weeks without my rebooting into MS or Apple.. or linux.. well..."that'll be the day. that I say good-bye" ;-)