I think the value and effectiveness of the golden rule as guide to ethical conduct is self-evident, so far as the individual is receiving equivalent treatment in return among peers. Yet, I have observed, that people who do not stray from the golden rule are often taken advantage of as they are perceived as being lame and soft prey for people with predatorial natures i.e. people who are taken advantage of and do not stand up for themselves, as they are either too afraid to, they find the prospect of violent retaliation undignified and demeaning to themselves, or they just couldn't be bothered arguing with fools constantly, etc.
Are there any Philosophers who address, in regard to the golden rule, the ethical treatment of people who cause harm to others, in terms as simple as the golden rule? And who is at fault, the person who does not follow the golden rule, or the person who, by following the golden rule allows themself to become a victim? It seems that an obvious resolution would be, if people don't treat you the way you'd like to be treated, then treat them how they treat you. But I think this would regress into "an eye for an eye" scenario, resulting in the whole world becoming blind, climaxing with, in the land of the blind, the one-eyed man is king, which would result in a total failure of the golden rule, which I don't find to be adequate.