The only ones who will leave are the very wealthy. Even then most of them will not want to do it. I remember when neighborhoods changed it was the renters who moved out first and then later the home owners moved. It is very hard to move to a new place, giving up a good job, home, schools and communities for the unknown.
All this is, is talk. The poor and elderly rely on government programs wouldn’t go. The middle class need their jobs and wouldn’t want to lose their house shuls, yeshivas and investments unless they fear for their lives. The only ones that can do it are the young singles who haven’t settled down yet.
Who knows if Canada will accept a large influx of Jews? Maybe there are the same problems over there.
How many of us will on the spur of the moment move to Israel? Sell your house at a loss. Transfer your investments out of the country for fear that the government will seize them.