Arabs have been murdering Arabs for hundreds of years. To say Israel started it is not only wrong but spreading misinformation.

"Israel" was internationally recognized as established in the 1940s based on a European movement from the 1800s to create a settler-colonial ethnostate. Israel did start it, it is an occupying force that displaced Palestinians from their lands in living memory, implemented violent apartheid conditions, and is currently doing a genocide.

Your "Arabs just kill each other this isn't different" is frankly just relying on racism to avoid actually addressing the real history.

Who started it is pointless at this point

No, it is very much an important point as it happened in recent history via occupation, terrorism, and forced immigration by European settlers backed by the British empire and then the US empire. You must ignore this in order to share the positions that you have.

but this anti Palestine sentiment from Israelis has been brewing for decades. For some context look up Arab-Israeli war of 1948

Anti-Palestinian sentiment has been a core part of the Zionist project since its inception. 1948 is when the largest expulsions happened, the war was a response to this occupation and aggression.