@IWFH
By your logic is a murderer who kills 10 people 'worse' than one who kills 9?
Yes, all else equal.
Your intuition seems to be that there's a certain level of badness beyond which it all really makes no difference.
But it clearly matters, both for the people harmed and for simple truth and accuracy, without which we can't make sensible moral or practical judgments. We're just MN commentators, but people who have the responsibly to take decisions need to see things clearly. If it turned out that Israel had fabricated three-quarters of their civilian death toll that would massively matter (you said 10k vs 40k deaths makes no odds, which is why I'm using a fourfold example). When there were horrible stories about how Israelis had been killed, it mattered whether those stories were true or not. When there are allegations about IDF behaviour, it matters what is true, what is false, and at what scale. I don't see how we can make any sensible conclusions about anything if you just round it all up to 'horrible' and then conclude your preferred conclusion.
Your accounting system could equally be used to 'prove' that Gaza doesn't matter at all: after all, it's a rounding error in the history of the world. After the Yemen death toll, why would 40k (using your number) matter? Aren't they just the tenth murder victim, morally irrelevant?
I say clearly not, this stuff matters. Whatever way you think the evidence points, evidence and accuracy matters. And the horror of an innocent death is as great whether they are the first or tenth or hundredth. There's no point beyond which it just doesn't matter.