Yes, the Palestinians would've been infinitely better off now if the Arabs had concluded a comprehensive peace treaty with Israel in 1949 or the early fifties. (While I'm on the topic of hypotheticals, they also would've been far better off if they had been all alone without any Arab "brother nations" to "help" them... for all the rhetoric, the Arabic countries haven't really given Palestine so much aid as to cancel out the massive disservices they've done them.) And since then, as Abba Eban so brilliantly put it, "they've never missed an opportunity to miss an opportunity" (the really sad part is he said that over thirty years ago, and they've missed a great many more since then). But that doesn't help us much now.