I believe that a real, strong and fair International Rule Of Law would help Palestine and that the two-weights-two-measures kind of Propaganda used of performative "International Rule Of Law" detracts from it Globally being real, strong and fair.
I don't think a performative demand for "Justice except if the perps are our mates" from the most hypocrite country leadership around will advance the cause of International Rule Of Law even when it comes to the Russian invasion of Ukraine because it just reinforces the impression outside the West that the "Justice" of the West isn't really Just or even honest - it's a great way to (as is it's only real objective) to get kudos from a certain crowd that abhors what Russia is doing whilst not having a tendency to look beyond the superficial in a skeptical way for even the words one agrees with, but comes with the secondary side effect that people in all those nations out there which are not aligned in this specific subject just become more suspicious of Western words and motivations and hence less likely to cooperate.
Such performative statements for local political gains neither advances the cause of Global Humanitarianism nor the cause of International Rule of Law, probably the opposite.
Such idea would much better be voiced by a different country (say, Spain), not one practicing the very opposite of what it preaches and with quite a long tradition of being double-faced.