Rosanne already is world famous and has many millions of dollars. She doesn't NEED a TV show…especially one that she knows would have been politically muted if she tried to keep going the way she was going. They likely told her that they were going change the content to eliminate the pro-Trump stuff, and she was also likely told that she had to accept it or that there would be no show. So, she told them to fuck off and crashed the bus on purpose. Many very famous actors were offered similar 'take it or leave it' deals by the suits who run the TV networks and quite a few of them crashed the bus and walked away too. This is almost always what happens when a very successful show is suddenly canceled and the actors' careers are pretty much done after that. Angela Lansbury said that's what happened to her on Murder She Wrote too.
You cannot really openly have a politically conservative point of view and thrive as an entertainer on ANY of these commie TV networks. They are owned by multinational conglomerates that serve the interests of the cabal.
Rosanne isn't stupid. She knew what she was doing. She had to have anticipated the consequences. She simply made the decision to go out on her own terms.