The settlers that currently take land from Palestinians on the west bank, those specific people, not some group centuries ago that those people might share some part of their identity with, were not there before the specific currently living people that they are taking that land from. People living now matter more than some vague historical claims. If the area had been invaded by Islam and the land taken from Isreal within living memory, then sure, it would be just that it be returned to those it was taken from, but taking the land from people who have been there generations to give to people that have not been there for that time and had established lives elsewhere, results in people being uprooted and forced from their homes needlessly. Any history along the lines of what religion was where first is irrelevant to that fact.