I think you got some of that wrong.
According to "A Saucer Full of Secrets" by Nicholas Schaffer, the band was on agreement on firing Richard Wright during the Wall production, because at that point, the guy was so fucking high on drugs he couldn't work.
The line in "Nobody Home" - "I've got nicotine stains on my fingers, I have a silver spoon on a chain, I have a grand piano to prop up my mortal remains" was a direct reference to Wright's drug issues. And this wasn't a small thing to Waters and Gilmour, Syd Barrett had pretty much self destructed due to his drug issues. (Barrett would die in 2006 and Wright in 2008).
Mason and Gilmour didn't kick Waters out of the band, they all split up to pursue solo products. But then Gilmour realized he couldn't sell anything without the Pink Floyd label on it. So they sued Waters over the use of the name.
And frankly, anything they did without Waters was kind of crap.