I am a Bear fan --- not necessarily a Cutler fan.
Jay has diabetes and I think blood sugar fluctuations affect his performance and demeanor. I think Jay comes off as disinterested as a result. However, from what I see publicly, I have no reason to believe he is not a good person. He is involved in local charities and seems to be a good father and husband.
I hope Jay succeeds this year, but if he doesn't, this will be his last year in Chicago.
https://www.chicagobusiness.com/article/20150831/BLOGS04/150839998/heres-how-much-people-dislike-jay-cutler