> Do you think that post disengagement Gazans live under "apartheid"?

Yes bantustans were an important part of apartheid, and Gaza is a bantustan on steroids. Both South Africa and Israel disclaimed responsibility for their respective bantustans, but at least South Africa at least formally granted them independence and (unsuccessfully, to be sure) tried to get them international recognition and engagement.

Israel, while disclaiming responsibility, also takes active diplomatic steps to deny Palestinian territories recognition as independent and actively seeks to thwart any international engagement with them.

The parent post didn't even mention Gaza (simply said "Israel is an apartheid state"), and you were the one who brought up lives of Israeli Arabs. For your question however, I don't think that apartheid is a suitable term to describe the terrible conditions Gazans are living in.