People aren't leaving Gaza because there is no fuel of transportation.
People continued to flee after that IED exploded. That isn't the reason that people are not leaving Northern Gaza.
The hospital explosion wouldn't be an example of something that would keep people in Northern Gaza, if anything it would make them want to leave, regardless of who they believe was responsible.
Maybe there is no fuel or transportation because Hamas is using what little they have for themselves.
It doesn't matter to me. Israel is choosing to drop bombs that they know will kill civilians because they are angry. Israel is less safe today than it was on 10/8.
They might take out Hamas, but every kid in Gaza is going to grow up hating Israel far more than they would have otherwise even. Whatever replaces Hamas will be much worse. The only way this ends up making Israel safer in the long run is if they kill everyone in Gaza.