How does that follow? Aren't some farmers better than others? Do humans always function at the best of their abilities? I live in Los Angeles. We have very little agriculture here anymore. Yet our population is large and still growing. Much of what you say here is shaky. And irrelevant.
Did the land become more productive after the Jewish settlements became more numerous?
Yes.
Did scores of thousands of Arabs immigrate to the Holy Land from elsewhere in the Arab world?
Yes.
Do these people make up the bulk of the ancestral population for the so-called "Palestinians.
Also yes.
So are the ahistorical claims of the "Palestinans specious?
Bingo.