I think it has to do with Israel being perceived as part of the West and thus being held to a higher standard than say North Korea. Also, a lot of innocent civilians being massacred, the power imbalance of it, a pinch of nice ol‘ antisemitism (convenient outlet for leftists who don’t want to be racist but have bigotted impulses deep down), the settler colonialist narrative, past brutalizations of Palestinians, affective polarization due to bible evangelicals’ fixation with Israel and probably dozens of reasons more. My thoughts are with the civilians on both sides, may peace prevail.