That case was one among many that established the primacy of Federal Civil Rights law over local law and custom. You may happen to agree with that ruling, but the end result of it and others was that a local government today has difficulty doing things like banning Drag Queen Story Hour at the local library. They may not have to fund it, but they can't stop it if someone else does. At least not without risking a lawsuit from this same ACLU.
Hell it used to be a trope in 90s television where police and right-wing characters would blame the ACLU for not being able to do something, either because they'd fought it in court or would fight it in court. A powerful position to be in.
To answer your question, they do it the same way they override freedom of association to combat "racism". Liberal principles are vague, so they promote some and subordinate the others to get whatever pre-determined outcome they want.
That case was one among many that established the primacy of Federal Civil Rights law over local law and custom. You may happen to agree with that ruling, but the end result of it and others was that a local government today has difficulty doing things like banning Drag Queen Story Hour at the local library. They may not have to fund it, but they can't stop it if someone else does. At least not without risking a lawsuit from this same ACLU.
To answer your question, they do it the same way they override freedom of association to combat "racism". Liberal principles are vague, so they promote some and subordinate the others to get whatever pre-determined outcome they want.