The problem is: it doesn't matter. The point is that Arab Jewish people are in Israel now, by the millions. The issue isn't that they've won some kind of trauma competition; it's the simple practical fact of their presence and the history that brought them there.
Your second point, about MENA "nations" expelling Jewish people "in a vacuum", is deeply concerning. No matter what Israel did in Palestine, Arab Jewish people had no culpability. Arguments like this are why the distinction between criticism of Israel and outright antisemitism are so slippery. I too think that distinction is weaponized, but it's hard to press the point when you're making facially antisemitic arguments.
How does something occurring in Palestine justify this? Tying the actions of Jewish militias to your local Jewish population is antisemitic… if they expelled them to protest the creation of Israel, then that isn’t anti-Zionist. That they mostly all ended up going to Israel is ironically supporting the Zionist cause
We cannot question their allegiance?
If an Iraqi did the same thing when the U.S invaded Iraq, you wouldn't question their loyalties?
Arab countries are within their right to question the allegiance of their population when their local population is conspiring (or suspected) against their national interests.
Do I need to remind you the Japanese internment camps in the United States?
It's 1956, it was before the mass surveillance era, internment and expelling was a valid solution when you stop a literal terrorist plot.