Andrew, the Lukan nativity songs seem to express what might have been if Israel and its leadership had accepted rather than killed their Messiah. As such there is nothing about a child born to die for Israel’s sins.
So do you think that when Jesus first started announcing the kingdom of God in Galilee he had any intention to die/die for sin? If not, when and why did Jesus’ plans change? Or was it the post-resurrection disciples who reimagined the Messiah’s mission?