Gaza was "unoccupied" on October 6th, 2023.
There is a school of thought that thinks "occupation" is defined as the effective control of a foreign territory by a hostile armed force--- and an outside force installing armed checkpoints, closing all avenues of travel, controlling employment, electricity, water, medical supplies, food deliveries, exercising an authority to move the inhabitants at will, and demanding "quiet" in return ---- meet this definition, even if the occupiers decline to live there.
One can certainly disagree with this, but that may no longer be enough to stop this school of thought from winning the debate.