If that border was fully under control of Egypt, there would not be a trickle of aid in, but hundreds of trucks would be passing through. Egypt is bound by some agreements, too:

https://www.washingtoninstitute.org/policy-analysis/new-real...

Anyway, occupying power can't displace occupied population to other country, for any reason, without violating Geneva Convention:

https://ihl-databases.icrc.org/en/ihl-treaties/gciv-1949/art...

Not that Isreal cares, but rest of the world does.