3) I dont think you can change a “fan of a characters” mind, by bashing said character to death- if anything their love of the character usually deepens because they feel the need to protect them more, but the people doing the bashing become resented & respect for them declines. However, I do think you can change how other fans feel about certain character’s by doing the opposite- totally ignore his/her flaws, put them up on a pedestal & it tends to eventually drive people to distraction- they tend to start disliking the character, as well as resent those doing the OTT PR for them.
Totally they can. I’ve been put off Neal and to a certain point Regina by the viciousness I read by the toxic part of their fan groups – and obviously I don’t include all fan in this, because by and large like with everything, there is always a small faction that spoils things for everyone.
I definitely agree with both of you–when hard-core fans of other characters say ridiculous, exaggerated, and/or completely false things about my favorite characters (usually Hook draws the most hate of course, but also Emma), it makes me like those first characters less and less.