I don't agree with the presupposition that this conflict can be viewed from a starting point of Oct 7th though. These events didn't happen in a vacuum, Hamas didn't appear overnight, and the Palestinian issue isn't something recent. There's a long continuous thread of incidents that led to Oct 7th, and I have no doubt that that date itself will be considered another flashpoint over the next however many years.
It's why I think framing discussion from a "on Oct 7th" is disingenuous. The circumstances that predate Oct 7th, (illegal occupation, blockade, subjugation and dehumanisation) led to October 7th, and not the other way round (again this isn't justifying it, but just explaining it before I'm misquoted). I said in an earlier post that Hamas could become obsolete, almost overnight, if Israel were to agree to a 2 state solution with the PA for the West Bank...think about the optics and wider political implications for Gazans if that were to happen. But we know Israel don't care about a 2 state solution, and instead want to atomise the West Bank, as well as brutalising, murdering and removing any Palestinian presence in the land.
Also your figure of 1,500 is inaccurate - the Israeli side still haven't confirmed it but best present estimates have it at the ~1,200 range.