It’s both actually. The Servant is a metaphor for Israel being discussed as a person. The text even says, “My Servant, Israel”. This is not hard.

Here is where your hermeneutic runs into contradiction. When GOD discusses chastising the Servant for their SIN, is GOD saying Jesus was sinful? That doesn’t work for Christian soteriology. You need to maintain consistent CONTEXT in translation. You cannot flip-flop context because it suits a flawed hermeneutic.

Just trying to help out here. :)