How many viewers do you think ABC would have lost if they had left Roseanne on the air?
Do you really think this is about business or money?
The NFL learned that lesson with the kneelers.
I don't think they've learned it yet, but the distinction here is that the NFL audience found the behavior quite offensive and it has cost the NFL millions to indulge the trouble makers.
I doubt Roseanne's audience, or ABC's audiences in general would have declined at all. If anything, even more people might have tuned into to see what Roseanne did next in her show.
I would bet that ABC would overall have gained viewers. No, this is not about the tweet. ABC is determined to send a message to celebrities and others: Look what will happen it you are pro-Trump and/or dare to criticize the stars of the Left.