I think if Fawcett had demanded more money she would have got it. It was more likely she quit after one year because she wanted to show she had the acting chops for more serious roles (which she pretty much did)
Charlie's more like Suzanne Somers of Three's Company (and nothing much else), where it was about money.
Charlie? Well anyone who states their ambition is to "make movies with superstars", should probably not be relying on acting.
No, she didn't get it...that's what I already said. Her showdown didn't work.
Farrah didn't get a whole lot of serious roles later...just a handful. She was more a celebrity than actress and a lot of the celebrity she got later was because of the scandals in the O'Neal family.
Shows like that are few and far between. The only other star who probably could have pulled that off since then is Jerry Seinfeld, after the fourth or fifth season of Seinfeld.