The intent is that FD should only be applied in extremis. This could be read as meaning when there are no volunteers, and so straight draft would have to be offered to all volunteers first.
At the moment FD is very frequent because there are not enough pilots, and so it seems they are taking no chances and Forced Drafting absolutely anyone they can get hold of! This then makes the situation worse because even the volunteers want to have the option to refuse certain trips. So now they are turning off their phones too, exacerbating the problem further.
It is a can of worms.