Yet plenty of old testament prophecies predict Israel’s return. Paul making a point about spiritual Israel doesn’t void those prophecies.
One needs to understand these promises in light of the revealed truth of the New Testament. Paul explains in several epistles who the Israel of God is.
Paul explains in Romans 9 that "not all Israel is of Israel." Membership in the Israel of God has nothing to do with ones flesh.
6 Not as though the word of God hath taken none effect. For they are not all Israel, which are of Israel: 7 Neither, because they are the seed of Abraham, are they all children: but, In Isaac shall thy seed be called. 8 That is, They which are the children of the flesh, these are not the children of God: but the children of the promise are counted for the seed. (Romans 9:6-8)
And who are the children of promise? Paul answers that:
16 Now to Abraham and his seed were the promises made. He saith not, And to seeds, as of many; but as of one, And to thy seed, which is Christ.
29 And if ye be Christ's, then are ye Abraham's seed, and heirs according to the promise.
The promises were made to the true Israel of God. There is only one. And it only consists of those who are in Christ. The only way ANYONE can be a part of Israel is to believe in Christ. As Paul further explains:
But the Scripture has shut up everyone under sin, so that the promise by faith in Jesus Christ might be given to those who believe. (Galatians 3:22)
That country over in the middle east which calls itself "Israel" is NOT Israel. And no promises were made to it.