A successful campaign of Hellenization in the Levant would not lead to the elimination of the Jewish people as a distinct cultural identity, although it would most assuredly change it dramatically.
It certainly could, though.
Eliminating an ethnicity in one fell swoop is difficult, but over time, it's very easy. The Jewish religion could very easily have been absorbed into some other religious movement, and the language, being closely related to other Semitic languages of the time, would go extinct, as it
did in our own timeline.
In all honesty though, I believe that it is the persecution of the Jews that has made them persevere so diligently over the centuries to preserve an identity that others didn't want them to have. If they're not persecuted, it could be very easy for them to amalgamate into one of the other Semitic groups in the area. Even with the current POD, without the death of Jesus to blame on Jewish clergy, they probably wouldn't be prosecuted to nearly the same extent where they went, and could possibly be absorbed - the way Greeks in Spain, Sicily, and Southern Italy have mostly been absorbed...