Stories like this often get flagged because they devolve into political/religious flamewars. I think many people might have a knee-jerk reaction to posts about the Israel/Gaza war and flag them, because support for Israel vs. support for Palestine can be quite polarizing and emotional.
Not saying it's right or wrong, or that this sort of article is or isn't interesting to HN readers. But a reasonable reason for flagging an article is a belief that the topic at hand doesn't lend itself to thoughtful, interesting discussion.
If a current genocide by the same people who claim they had a genocide commited against them, isn't a subject that lends itself to thoughtful discussion then I don't know what does.
No the reason you can't talk about it is like with any other genocide, the propaganda machine first makes sure to silence all people that might point to its crime, then it proceeds with the said crime.
Flag or delete this comment or this account, 4chan had been tamed with bots, HN well has become a slightly higher IQ reddit, etc. the internet is dead.
People are constantly implying the Russians invaded Ukraine for no reason, or that Iran is the aggressor in the recent war, or that a genocide isn't actially happening.
Haaretz is generally a liberal Zionist Israeli newspaper. As such, I find it easy to trust that it is not lying when it reports sensitive testimony from multiple IDF soldiers.
I wouldn't say it's thoroughly off-topic because not only do a lot of tech companies directly enable or produce the stuff that's enabling Israel but a fair number of major figures have also directly involved themselves politically with Israel.
That said it's the kind of topic I don't expect HN to be able to particularly handle in an interesting or insightful way. It's mostly just going to be a mix of horrified people and then users trying to gaslight others into how this is a good thing.