The first question was rhetorical, the point being, as you acknowledge, that neither side abided by the U.N. resolution. Given that posture by both sides, it should surprise no one that the post-war division of the land was not the one in the U.N.resolution.
The consequences you suggest would simply have let the Arabs live to fight another day, which there is no reason to believe they would not have done. Maybe if the losers had convincingly acknowledged the winner's right to exist, different borders would have been established. I don't pretend to know. Do you?
I am not justifying any action that the Zionists/Israelis took or are taking. I just don't think it matters to the question of how the Palestinian Arabs should have spent the last seventy-five years. As some black American say "It's their fault, but it's our problem." The Palestinian Arabs have not solved their problem; they have only exacerbated it. Rehearsing who did what to whom just encourages their continued failure to make peace with reality.