Yes Israel dictates what’s goes through. Gaza* has proven again and again that they cannot be trusted to just import whatever they want, because the corrupt everything Hamas touched and turn virtually all civilian infrastructure into instrumentalities of terrorism.
If your neighbor was suicide bombing you and rocket attacking you and mass shooting you, do you think you’d let the UPS truck in to deliver whatever they want? No. You would not. The police would come and if they didn’t surrender they’d level the house.
But that’s not even what’s happening here. Gaza opened new water desalinization plants just last month. Israel let the materials and personnel in.
Edit: I should say, Gaza didn’t build new shit, western charity built new water desalinization plants Gaza.