It makes perfect sense if you read up on the history of the conflict, particularly over the last 30 years.

Palestine's reward for trying to find a diplomatic solution has been Western-sanctioned destruction and massacre every single time. We westerners have largely ignored that their land has been taken, hospitals and infrastructure bombed, news reporters and civilians shot in cold blood, and no meaningful repercussions for any of it. They've even been blockaded for sixteen years.

Think of it like a smaller-scale Tet Offensive. It didn't seem to make a ton of sense for the Vietnamese to launch an offensive against the South Vietnam and their powerful allies either.

And when you consider how unreasonable it is for 1.1 million people to evacuate in a day, remember also that these people aren't allowed out in the first place.