It has more legitimacy than Christianity in the eyes of Rabbis. Muslims are more likely to go to "the world to come (next life)" than Christians according to Rabbis
I don't care about Rabbis whose views are as broad as any Christian pastor. What do Jewish scholars say?
The Jews were chosen by Allah but that changed after taking the lives of some Prophets.
[2.47] O children of Israel! call to mind My favor which I bestowed on you and that I made you excel the nations.
[2:87] Certainly, We gave Moses the Book and followed him with the apostles, and We gave Jesus, the son of Mary, manifest proofs and confirmed him with the Holy Spirit. Is it not that whenever an apostle brought you that which was not to your liking, you would act arrogantly; so you would deny a group [of them], and kill a [nother] group?
There are a couple of more verses in the Quran that also mention this. This is true according to the Bible.
The spirit of God then invested Zechariah son of Jehoiada the priest. He stood up before the people and said, ‘God says this, “Why transgress Yahweh’s commands to your certain ruin? For if you abandon Yahweh, he will abandon you.” * They then plotted against him and, at the king’s order, stoned him in the court of the Temple of Yahweh (2Chronicles 24:20-21).
Elijah responds: “I am full of jealous zeal for Yahweh Sabaoth, because the Israelites have abandoned your covenant, have torn down your altars and put your prophets to the sword. I am the only one left, and now they want to kill me” (1Kings 19:9-10)
That is one of the reasons the final message was revealed through Prophet Muhammad PBUH. They lost their position and Muslims (regardless of ethnicity) gained it.
One of the characteristics of God that Christians understand is his omniscience which means he is all knowing.
Which means that he knew, in the beginning, of the waywardness of Jews when he proclaimed in Genesis 3:15 "And I will put enmity between you and the woman, and between your offspring and hers; he will crush your head, and you will strike his heel.'"
Which was the first prophecy that God made of the Savior who would come to redeem mankind.
And yet, in his omniscience, he still elevated the Jews above all nations.
God is not fickle and does not take back gifts and covenants that he bestows.
Your characterization of God forsaking the Jews for Muslims doesn't make sense in any context. Because when God forsook the Jews, what did he do? He brought along another prophet
from among them to reign the Jews back in so that his Will could be done, which was the Word being made flesh
from among the Jews, the revelation of God to the world.
You are pulling out scriptures talking about Jews forsaking God and killing his prophets, but the scriptures that you're pulling disprove what you say. You point out Zacharias and the Jews stoning him, and in the same breath mention Elijah. Did God not send Elijah to the Jews? Elijah came after Zacharias so clearly God didn't forsake the Jews in the way that you think when they stoned him. Elijah, another prophet, was sent. Not only was he sent, after Zacharias, another prophet, Malachi, was sent before Elijah even came.
And we know Elijah was sent to prepare the way for the highest Prophet.
One of the biggest themes running through the Old Testament scriptures is bloodlines and genealogy. God proclaimed in Genesis the 'Seed of the woman' emphasizing that fact.
God would not have brought the Jews out of slavery in Egypt, performing miracles never before seen, smiting the Egyptians, rolling back the Red Sea, rolling back the Jordan River, collapsing the walls of Jericho, all knowing he was going to abandon the Jews for a group of people not having the right bloodline. God killed off other nations and bloodlines for being defected.
He had a Will. That Will had to be complete with Christ. And it was done through the bloodline of the Jews.
After that, the Holy Spirit is sent to be God's presence in the world after Christ ascended.
You Muslims blaspheme the Holy Spirit claiming him and his works are that of Muhammad.