Not sure what the correct move for egypt is in this situation. Build a wall and israel blows up all the palestinians, let them through and the imperial core blames you when they die of exposure on the northern end of the sinay peninsula. The only egyptian settlement near the border is sheikh zuweid which is a fraction of the size of rafah and would likely be completely overwhelmed if palestinians were let through, and it looks like its just in the middle of the desert otherwise.

I dont know how feasible it would be to build a refugee city in short notice on the egyptian side of the border, and I have my doubts that any government who could afford it would be willing to fund it.

Looking at it from a realpolitik angle, perhaps egypt has more to gain by letting the palestinians die. Palestinians would likely continue their struggle within egypt if allowed through, but if confined to gaza israel may eventually murder enough of them that organized resistance is no longer possible. In that case, I imagine more military effort will be focused on the destruction of yemen, and because of how reliant the egyptian economy is on suez canal tolls, they would stand to benefit from the destruction of organized houthi resistance and the resumption of trade through the red sea.