Free will is one thing. Agency is another. If I want to, I can take steps to try to work toward becoming a leader, or a champion, or a fiend. Slaves can obey, or they can face discipline for disobedience. Those are their options.
From a simple baseline, the natural state of existence is one of pure agency: you can attempt whatever you are actually capable of attempting. Society, however, requires some abrogation of this state of natural agency in order to function. The classic example is: I agree to waive my natural right to kill you and take your stuff, and in exchange, you agree to waive your natural right to kill me and take my stuff. True cooperation is achieved only when both sides voluntarily limit their natural agency in order to promote greater achievement in mutual pursuits. It is this foundation upon which all of society rests.
Limitation of agency comes about either as a result of such voluntary choice, or from an imposition by an external force. When it is the latter, there then must be justifications for it which are beyond question, else it is oppression. The limitation of the agency of children, for example, is justified by the child not being in a position to make properly informed, well-reasoned decisions regarding complex issues which often require long-term perspectives and experience.
Imprisonment of criminals is justified in their past behavior. The choice of using their agency to inflict harm on others violates the basic social contract upon which society is built. This demonstrates that they will put their agency to use in ways that actively infringes upon the agency of others. As a result, in order to preserve the greatest amount of agency among the greatest number of people, those who intentionally curtail the agency of others have their own severely curtailed.
Oppression—the forceful limitation of agency upon others against their will without unimpeachable justification—is an offense against society. It is such because society is predicated upon cooperation. We work together, rather than killing one another and taking one another’s stuff, because the benefits of doing so outweigh the inconvenience of not being able to take whatever we want. When members of society are oppressed, this undermines that core premise: some members of society are expected to abrogate their natural agency without receiving the same benefits and protections as others.
This becomes actively detrimental to society in the long term: if a justification that is not indisputable can lead to the restriction of one person’s agency, then no-one is safe from such justifications being fabricated to use upon them. As a result, all members of society, whether they recognize it or not, are threatened. Those who do recognize this quickly begin to mistrust those in authority.
Those who do not recognize the threat will also, if less swiftly, come to mistrust authority as elements of the general mood begin to plant the seeds of (completely justified) concerns in the undercurrents of conversation. Topics will become forbidden, or ‘dangerous’ to talk about. Conversations will hush and go silent when the enforcers of authority—police forces, for example—draw near. Even if people do not recognize why these things happen, they will know that they do happen, and this will further foment mistrust in other members of society.
In short order, you have a society where fear of reprisal, not the benefits of mutual cooperation, is the primary binding force… and such societies will always experience greater stress on their members, less fulsome cooperation, greater inefficiency, schism, and ultimately collapse. Usually, social dynamics of this sort are only able to endure when there is an external threat or challenge to focus frustrations on, in order to appeal to greater social unity in defiance of the ‘other’. Lacking this hob-goblin, the need for an oppositional force to define oneself against turns inward, accelerating factionalization, paranoia, and strife. The longer such tensions are kept locked down, without a way to release pressure or work toward constructive resolution, the more likely a society is to experience cataclysmic upheaval.
Care to expand your rebuttal beyond ‘but whyyyyyyyy?’ in response?