Ancient history is irrelevant here. The Bible is not a property deed. The middle east has been fought over and conquered again and again since Gobetiki Tepe, some 7000 years + before the supposed life of Abraham. So there is no point on this topic.
Regarding the Zionist movement. Yes, much of it was very legal — the Jews in Palestine were always a small minority, but there was legal immigration and properties were exchanged. However, this was a very small amount.
Most Israeli property was obtained not legally, but through war or various economic pressures to ethnically cleanse without compensation. This military conquest of Paleastinan land began in earnest even before the 1947 war (look up Haganah’s Plan Dalet, or the terrosism of Irgun Lehi, Stern Gang, etc.).
Israel, as a government has run an apartheid state. It does not give people of a different race/sect/religion, etc. equal rights or services. It is a racist state.
So I dont care who lived there 5000 years ago. What matters is that lands were forcibly stolen, never compensated for, and the victims continue to live with grave and continuous violations of human rights.