I do not see any limitation which would mean jews only
John 12:47 (KJV 1900) — 47 And if any man hear my words, and believe not, I judge him not: for I came not to judge the world, but to save the world.
here world includes any unbeliever
you just ignore scripture
Jesus was prophesied TO and FOR Israel (Deut. 18:15, 18), He was manifest TO and FOR Israel (Jn. 1:31), He was sent only TO and FOR the lost sheep of the House of Israel, came and taught the lost sheep of the House of Israel, died and resurrected according to the Scripture shadowed in the sacrifices of the Tabernacle and Mosaic Law and saved "His people" (Matt. 1:21), and in the three Hebrew covenants there are no Gentiles included in the three 'limited' salvation Hebrew covenants.
John, as well as all the New Covenant writings from Matthew to Revelations were written TO and FOR the children of Israel and the context of and identity of the "any man" in John are of the Hebrew people He came to save.
But Gentiles have tried to weasel their way into God's three specific and closed Hebrew covenants since the destruction of the Jewish Temple. That's called inheritance theft, also known as tomb raiding. Gentiles have no inheritance from God because God made no covenant promises with Gentiles. God doesn't even like the unclean, uncircumcised, non-covenant, non-Hebrew Gentiles:
17 All nations before him are as nothing;
And they are counted to him less than nothing, and vanity.
Isaiah 40:17.
There is no Scripture in the Law, Psalms, and Prophets God loves Gentiles. But there are 37 books of the Law, Psalms, and Prophets of God declaring His betrothal to Israel, calls Israel His Church and apple of His eye and declares many times His love for His marital covenanted children of Israel:
6 For thou art an holy people unto the LORD thy God: the LORD thy God hath chosen thee to be a special people unto himself, above all people that are upon the face of the earth.
7 The LORD did not set his love upon you, nor choose you, because ye were more in number than any people; for ye were the fewest of all people:
8 But because the LORD loved you, and because he would keep the oath which he had sworn unto your fathers, hath the LORD brought you out with a mighty hand, and redeemed you out of the house of bondmen, from the hand of Pharaoh king of Egypt.
9 Know therefore that the LORD thy God, he is God, the faithful God, which keepeth covenant and mercy with them that love him and keep his commandments to a thousand generations;
Deut. 7:5–9.
Nowhere in the Law, Psalms, and Prophets does the LORD declare Gentiles/nations holy, special, elect, "above all nations of the earth", His Bride, His Church/Great Congregation, nor extend His provision, His covenants, His protection, His deliverance, nor love for Gentiles.
But the Bible states time after time those things and attitudes towards Abraham's seed the Children of Israel.
When you come to understand and accept these things as well as the history and involvement of God with the Hebrews because of His Promises to Abraham, Isaac, and Jacob, then you move closer to the knowledge of the truth.
The gospels record highlights and points of Jesus Christ, Redeemer, Deliverer, and Messiah and His relation with Israel "so that [they] might believe." But now we know that no one can believe unless acted upon them by God. But Israel has covenant with God and one day "all Israel shall be saved."
The epistles are written by Jewish Christians TO and FOR other Jewish Christians and the purpose was to share what they learned and discuss and reveal Israel's understanding of the New Covenant Era they found themselves in from Pentecost until the death of John. They had to "search the Scriptures" to reconcile the effect of Messiah and the Holy Spirit of Promise (to Israel) and their relationship to the Abrahamic and Mosaic Covenants, and this took time, much reflection and study in order to bring about a historical and Hebrew understanding of this salvation which is of the Jews.
Saul, after his repentance disappeared for 14-17 years with his books to do just that, and as a trained rabbi he searched the Scripture of the Law, Psalms, and Prophets for the understanding revealed in his letters to the Jews and was successful.
Revelation is prophecy about things to come upon Israel in the last days at the hands of Gentiles and their eventual victory over their confirmed enemies the Gentiles. Everything having to do with Israel's promised Redeemer, Deliverer, Savior, and King centers around the nation and people of Israel.
NOT Gentiles.