I would question what “ties to militant groups” actually defines.
Is it active support of known Hamas-members? Or is it more like aidworkers giving school supplies to the school of the daughter of the 3rd cousin of the brother-in-law’s grandmothers brother, who once had tea with someone who might be a Hamas member?
Because Gaza is contained in itself and not big to begin with. Everybody is connected somehow. And if you count indirect contact as “ties to militant groups” you could easily get to 10%.
This number, even if true, doesn’t mean anything without definition.
When I did development work in Cambodia, I had contact with several former Khmer Rouge. They are part of the population. That doesn’t mean I was connected to their genocide.