Ransom is unusual among the atonement models in that it is defeated as a theory and undefeated as a language. Christians who hold satisfaction, penal substitution or moral influence still sing of being ransomed, redeemed, bought with a price and purchased out of slavery, and do so without embarrassment.
Part of the reason is textual. Ransom is not a theologian's metaphor imported to explain the cross; it is in the sources being explained. A saying in Mark and its parallel in Matthew has the Son of Man giving his life a ransom for many, the first letter to Timothy has him giving himself a ransom for all, and the Pauline letters repeatedly describe Christians as bought. A model can be abandoned; the vocabulary of the text cannot.
Part of the reason is that the word does work that the other models leave undone. Ransom names a condition, not just a status. It says that the difficulty was not only that human beings were guilty but that they were held, and that they could not have got out. Accounts built entirely on guilt and penalty describe a legal position; accounts built on captivity describe a predicament. Writers on addiction, on structural injustice and on political oppression have reached for the ransom language for that reason, and Christus Victor is in part an attempt to keep the predicament while dropping the transaction.
There is a standing methodological point here that the atlas takes seriously. A biblical metaphor is not automatically a theory, and pressing a metaphor for detail it was never meant to carry is how the recipient question arose in the first place. Some theologians therefore hold that ransom should be honoured as an image and never converted into a mechanism at all. Others reply that refusing to ask what an image means is not humility but evasion. That disagreement is live and is not confined to this doctrine.