Passing qualifications is a minimum bar (most of the time), the real test in an interview is proving to them that they would like working with you.

I kind of don´t even apply to social work jobs anymore. I know they are looking for people they can "relate" to and, surprise!, it's young college educated white women with long hair who follow all the rules society's given them.

Specific to interviews, they expect you to follow social customs and exaggerate, if youre being honest then even if that shows youre a virtuous person (and they may even like you more because of it) it also means that you either cant follow social normals because you dont know how, or you refuse to (which might show issues with authority) and either way it will lead to problems in the workplace.

This is quite a long sentence, but I think you're just describing a Catch-22?