I definitely made an attempt to be as concise as possible.

I also agree that my answer at least immediately begs the question "Why is removing agency wrong?"

I think it's harder to be concise here because we're actually approaching territory where the answer starts to approach self-evidence. We're getting to premise. It's harder to argue for or against self evident ideas and premises because a good argument won't let you use the self evident ideas and premises themselves to argue for them.

Removing a person's agency cuts to the very core of what it means to be a sentient creature on this planet. With self awareness comes the ability to act and make choices based on that self awareness. Beyond just giving us the ability, agency is the primary mechanism by which we perpetuate our survival as a living creature. As humans, our survival instinct is literally manifest in our agency and the choices we make to further our own survival and interests.

Agency is the literal expression and manifestation of the human survival instinct.