It is because it broke down after the first delivery and the first delivery got blocked by the IDF and wasnt distributed. So the Pier didnt really deliver anything yet.
It is also still far too little and the US could force Israel to open all borders to let in as much aid as is actually needed by stopping to send them weapons and provide diplomatic cover. Plus if the US would apply sanctions, Israel could be forced to retreat from Gaza and finally start upholding international law within a few days.