David Bukay (the Founding National Myths author) is an out-and-out bigot, little he says can be trusted. Nevertheless, the "Palestinian narrative" even as characterized by its enemy, Bukay, more closely resembles the facts of the case than your denial that Palestinians are the descendants of Canaanites, and claim that modern Jews are "exiles" from ancient times and have a "connection to Palestine that goes much much deeper" (than the Palestinian one).
The facts are, until 1948 conquerors of Palestine, including the Romans, didn't commit mass ethnic cleansing. Most of these people of ancient Palestine (Jews, pagans) eventually adopted Christianity or Islam. It doesn't matter whether or not people immigrated to Palestine from other parts of the Middle East or the Mediterranean, they didn't displace the ancient Palestinians, they were absorbed into the population. Paragraph 3 of your above repaste from Bukay is largely non-facts.
Also, since people traveled around in ancient times, for trade or proselytizing, it's possible that modern Jews have a little bit of genetic heritage from Jews of ancient Palestine, but most their genetic heritage comes from people who converted outside ancient Palestine, much much later than the founding of Judaism.
Well, I expect lies from Zionists. I recommend reading "Palestine: a four thousand year history" by Nur Masalha.
I commend you on agreeing to allow "hundreds of thousands", which would amount to perhaps 10% of Palestinian refugees, to return. In my view, somewhat paltry and not a real reconciliation offer, but better than most Zionists.
I suppose most "liberal" Zionists like to think of Jews as "natural" to the region. I don't know they square such "naturalness" with forcibly expelling most of its indigenous population, but anyway, it's a Zionist religious belief, not based on science, but more on biblical ideas regarding God promising the land to Abraham's descendants and so forth. There were some Jews who could legitimately make the claim, but science says most of the heritage of most Jews worldwide is from peoples who converted long after the biblical era in places far from Palestine. They aren't any more "natural" to the region than French Christians.
For genuine reconciliation, liberal Jews need to stop attempting to force this religious view on Palestinians.