“But there’s always been only ONE people of God - those who have been saved by grace through faith in either the coming of or the arrival of Jesus Christ.”
Absolutely. My view entirely. We will all be one people. But the promises yet to be fulfilled for the Jewish people remain.
“God is not a man, that he should lie, nor a son of man, that he should change his mind. Does he speak and then not act? Does he promise and not fulfill?” Numbers 23:19
All the promises to the Jewish people involve salvation in Jesus Christ and inclusion in His one true body, the Church. They will return to the faith of their father Abraham. There is no greater blessing awaiting any people, Jewish or otherwise, than recognizing Messiah and shouting, "Hosanna to the Son of David! 'Blessed is He who comes in the name of the Lord!' Hosanna in the highest!" It’s been going on now for 2000 years.
And it won’t take a “rapture” to make it all happen.