If the destruction of Jerusalem and the Temple in AD 70 truly was "no big deal", why did Jesus bother to predict it? You seem to have trouble grasping what Paul's comments about how there is no Jew nor Greek, male nor female, etc. in Christ. Of course these distinctions exist. Paul is saying that it doesn't matter whether you are a Jew or a Gentile, man or woman, slave or free - to be in Christ. A slave who is in Christ is actually more free than a free man without Christ, because the "free man" is still enslaved to sin.
According to Paul, the true Jew / true Israelite is the one who is in Christ. Consider just these passages from Romans - 2:26-29; 9:6-9; 10:12-13; 11:25-27. I could go on with others, but thought sticking with just one book would be easier.
If I may ask, do you believe there is one "people of God" or two?