That is exactly what they are doing. They are calling it "voluntary migration" as if making Gaza uninhabitable makes it voluntary.
I have to disagree with you on this Joe Biden Has the Political Space to Push for a Cease-Fire in Gaza. He Just Doesn’t Want To. But even if cutting Israel off and calling for a ceasefire was a politically untenable position, it would still be the necessary one to take. It can't have the same consideration as something like student loan forgiveness.