I guess you missed the Arabs arriving as conquerors in the seventh century and there having been a Greek-speaking Christian population before that in your 2000 year claim for the Arabs.
Yes, Ashkenazim moved into the Ottoman province, and mandate Palestine from the 19th century through the early 20th, buying land and homes from the Arabs, Armenians, and others who lived there when they arrived, but Sephardic Jews had been there all along. And, most the inhabitants of Israel now have at least one Sephardic ancestor, either from the ones who were there from antiquity, or from among the Jews who were either formally expelled from Arab nations or who fled pogroms launched against them when Israel fought its War of Independence against the British and fought off the first Arab attempt to drive them into the sea. As I asked about the Greeks and Smyrna, the Germans and East Prussia and Circassians and their homeland, do the Sephardim who were expelled from or fled Syria, Egypt, Iraq, and Jordan have a right of return of the sort you claim for the Palestinians?
The Arabs are not indignenous to Palestine. They held it by right of conquest, just as the Romans did before them, and the Israelis do now.