The Jews were already saved by God. Christ brings the rest in thank God.
Jews were the choosen people and I don’t think God would turn His back on them for continuing to follow Him in the old ways.
Jews have a front door key, Christians have the side door key but thank God because we are not worthy on our own and would never make it to heaven without the Divine intervention.
Your statement does not correspond the the Bible’s account of either Jew or Gentile.
The writer of Hebrews had a wee bit different take on this than you seem to have.