Which is absurd. The atonement and scapegoat corresponds to Lev. 16, and Israel does not make itself an atonement for the wicked Gentiles, with the Lord laying the sin of others on Israel, but the suffering servant does so for "my people," Israel.
Leviticus 16 is completely non-sequitur.
God does also refer to the nations (non-Jews) as “My people” as referenced by Isaiah himself in Chapter 19:24-25.
“In that day shall Israel be the third with Egypt and with Assyria, even a blessing in the midst of the land: Whom the Lord of Hosts shall bless, saying, ‘Blessed be Egypt My people, and Assyria the work of My hands, and Israel Mine inheritance.’”