Sorry, that was sloppy writing because I was trying to pack too much information into too short a post.
No, all the Jews weren't killed or enslaved, and the Levant wasn't empty of them. After all, there were enough of them left in the Levant after the First Jewish War to participate in the Kitos War, and to stage the second "Jewish War" or the Bar Kochba revolt, and they even had a bit of a resurgence in the 600s, but they had no temple, weren't even allowed to enter Jerusalem, and they were much, much reduced in numbers. The whole focus of Jewish life moved away from the Levant.
Whether the Jews that remained in the Levant eventually became Christians, with some of them then becoming Muslims, it's a complicated, controversial subject, but I lean strongly toward the idea that rather than convert they just left. Under Muslim rule, my recollection is that there was only a relatively small number left in the Galilee, mostly scholars.
As for the diaspora Jews, there was the Kitos War, so there was a major "culling" of those Jews as well. Some of the figures for the dead are undoubtedly exaggerated, but there was massive slaughter on both sides. Some areas were virtually de-populated. Alexandria, which was such a center of Jewish life, was also affected.
What I was trying to say is that not only were they much, much reduced in numbers, but they also were no longer a unified people with a homeland of their own. It was a huge and terrible price to pay for all the internal conflict, which often times was actually a civil war, for the eventual control by the Zealots of Jewish destiny, instead of the more moderate Sadducees. That's my opinion, of course.
It's my own opinion that it was the Jews who gave the Romans the most trouble in terms of the conquered peoples. Once Britain and France were pacified, and Spain as well, there was Romanization and order. No so in Israel. Yahweh called them a "stiff-necked" people. I think that's right, but, as I said, they paid a huge price.