I don't think that anyone is leaving over a storyline or a character. I think we have taken hit after hit after hit in the past couple years. Gloom and doom, characters written so far off base that they are barely recognizable, storylines that drag or are so ridiculous, history of major characters being rewritten, cougar hook up after hook up, writers in, writers out, wash, rinse, repeat, and more.
It's a television show, something a person chooses to watch, not something they should be shamed for not watching. I used to love watching Law and Order SVU, but it faded for me when certain ones left etc. So now I love watching Chicago Med. And that's OK, it's entertainment, not a life sentence.