I keep hearing the words ‘brainwashed’ and ‘forced’... Could one not say the same thing about the American military? Most people who took part in ISIS did so of their own free will. My sympathies are few and far between.
Are you seriously conflating military conscription and being sold and traumatized for years as a sex slave?
Most Muslims who joined ISIS did so of their free will. Muslims who lived in ISIS controlled areas collaborated or cooperated or kept their heads down.
Yazidis are not Muslim. They are a small desert sect worshipping a god/angel/devil, with rigid desert mores - there is a pre-ISIS video of villagers stoning a teenage girl because she had a cell phone and might have talked to a boy.
But to Muslims they are kaffir, not even people of the Book, fair game to despoil. The kidnapped women and girls were not subjected to pressure to convert. If they became Muslim, they would have had some rights - to live as concubines, and not be passed from man to man.