The Jews were not in error for not being a gentile.Not the 'hyper-differentiation', but denying his Jewish heritage is correct.
Phl 3:5
Circumcised the eighth day, of the stock of Israel, of the tribe of Benjamin, an Hebrew of the Hebrews; as touching the law, a Pharisee;
Phl 3:7
But what things were gain to me, those I counted loss for Christ. Yea doubtless, and I count all things but loss for the excellency of the knowledge of Christ Jesus my Lord: for whom I have suffered the loss of all things, and do count them but dung, that I may win Christ,
Paul did count being a Jew as nothing but dung, so far as being a Christian apostle in the body of Christ. That he may glorify Christ in his new spiritual birth of God.
Gal 2:20
I am crucified with Christ: nevertheless I live; yet not I, but Christ liveth in me: and the life which I now live in the flesh I live by the faith of the Son of God, who loved me, and gave himself for me.
Judaizing is simply Christians still hung up on OT Israel and the natural Israeli-Jews. Whether demanding outward circumcision, or separating super-elite sealed servants of God, from the rest of the lowly non-Jewish Christian schlubs.
I personally believe much of it is relatively harmless, with just nostalgia for old ancient days coming back again, or perhaps lack of self-esteem or confidence as just another natural born gentile among so many others...
Their Jewishness was in no way a game changer either way.
Now ALL MEN CAN BE SAVED.
The elephant in the room is "covenant"
If you jetison the 2 wives, end times is a shallow study.
That is why all the confusion exists, and WHY so many stumble over the 144,000.