I think this ultimately boils down to a question of changing a strongly held belief. Technically possible, practically impossible.
Beliefs built on sound reason can be changed, but you need to trace its roots and all its dependencies, as well as well reasoned argumentation. Beliefs tend to have a lot of appendages that depend on it. Often takes a lot of work, but doable with sane conversation.
Beliefs built circular as 'good because good' or 'bad because bad'... well, good luck trying. Outside of some extreme event that forces them to look deeper or at all, I don't see much point in even talking about it.