When Steve Jobs left Apple in 1985, he wasn't forced out the way the movie depicts.
In the movie, Jobs and Sculley have an intense (and completely fictional) argument about why Jobs left Apple. Sculley accuses Jobs of spinning the story in the press to make it look like Sculley fired Jobs. A flashback scene depicts Sculley and Jobs in a stand off with Apple's board about who would resign if the other was fired.
Sculley says Jobs left of his own free will because he didn't want to let the company divert resources away from the Macintosh's development. That's only partly true.
In reality, Sculley and Wozniak have said that Jobs left of his own free will because he didn't feel supported by the company, not because Sculley threatened to leave if Jobs stayed.