Then how do you make sense of Paul saying "For not all who are descended from Israel are Israel"? If there is only one Israel then that statement would make no sense whatsoever. Obviously, all who are physically descended from the physical nation of Israel are Israel, yet Paul said that "NOT ALL who are descended from Israel are Israel". So, he was clearly referring to another Israel besides just the physical nation of Israel there. Why can't you be honest and acknowledge that?
According to the verse, that would make you Abrahamites, not Israelites.
You would be spiritual Abraham, not spiritual Israel.
Of course Paul is contrasting Israel with Ishmael. Then contrasting Israel with Edomites would be the next logical step. And many Edomites were mixed in with Israel claiming to be descendants of Israel.
It would be a foolish thing to take Paul in these verses to claim not all of Israel is descendant of Israel, if they were. But Paul was saying the spiritual blessing was in Abraham, and not in Israel at all. Israel was the lost sheep of Israel scattered around the world.
The reason being is that many were of Jacob, buy not of Israel, because being of Jacob was being of the earth descendancy, without the attached spiritual blessing passed down from Abraham.
Why would you equate being of Jacob is the same as being the spiritual part of Abraham? If you are not Israel, you are Jacob, not a Gentile. That would be Paul's point. Not that the Gentiles are now spiritual Abraham and that means spiritual Israel.
Gentiles are the direct children of God, just like Abraham’s descendants who are Israel, are the direct children of God.
Of course now, being Israel has no spiritual connotation. At the Second Coming, Israel will once again be directly chosen as the sheep out of Jacob the goats. Once again on earth the sheep and the goats will be who Paul is talking about. Not all of Israel will be of Israel. Some will be goats, probably the majority. Many see Matthew 25 as being 50/50. But some can point out a remnant perhaps only a third will be sheep. Of course you rip off this chapter as being the church itself, when it is not the church nor the division of saved and lost.
Matthew 25 is the same theme as Romans 11. In Paul's day it was his people rejecting the blessing. At the Second Coming it will be God rejecting the goats. Both are about people living on the earth, not past dead people. The OT church was already settled in Paradise when Paul wrote Romans. The NT church will already be settled in Paradise, when Jesus sits as King separating the sheep of Israel from the goats of Jacob.