I don’t think that’s their intention. Yes, his actions are going to make Kana fans not like him for a while, but these characters’ claims to likability can stretch pretty far and still snap back into place when it’s redemption time. I hate it from the other side, on behalf of Rana, but I’m sure come a few months time, I’ll be fine with him.
Like, the actual worst guy, Phelan, is already there. Adam’s pretending to be Billy’s friend while replacing his pain meds. Daniel attacked his dad. Aidan also punched his sick dad and carried on an affair. Tracy exists. Except for Phelan, because I guess imprisoning people for months and multiple murders is a hair too far, all are shown in a sympathetic light or are forgiven with some “explanation” for their behavior. Zee’s hurt and anguish will be highlighted and the general audience won’t turn on him too much (especially since outside the LGBT community, outing isn’t perceived as awful as it is). He’s just going to be seen as lashing out, unseemly in the moment but ultimately understandable.
It’s basically going to be the first time we see Zee be present in this storyline beyond being a Heck type placeholder for nice supportive husband. If you remember the Eva/Aidan/Maria affair, Aidan/Maria wasn’t given at all the same treatment as Kana, with Eva getting lots more time to be vulnerable and sympathetic than Zee, even before she found out, and then after she did, she plotted her revenge and pretended to be pregnant and let Aidan get all excited about being a dad. Certainly not a nice thing for Eva’s character, but she was also shown to be hurt and sometimes conflicted about her plan. Zee will most likely be similar, with alcohol exacerbating his behavior during the few eps where this all goes down, and his conscience and actual good nature showing itself pretty quickly after, even if it takes more time for the situation to be resolved for everyone.