I agree GLT, and I listened to, and watched, a Video from a Psychologist who had worked extensively helping people who did want to leave High Control groups, and she said exactly the same as you.
A wise man said "When the Student is ready, the Teacher shall arrive".
We need to make sure we are equipped thoroughly to be that Teacher, as opportunity arises. It needs to be done with great skill and empathy, along with compassion, or we may do more harm than good.
Also good judgement needs to be exercised, some people are simply not equipped to leave, either emotionally, or in some cases financially, they also may well lack the Social Skills to join the real World of Normal People, and hence will struggle to make new friends, and hence will have no support, having lost all of their "friends" and associates, their Support Network.
But I do feel that as time goes on, we will be able to help many to leave, as you so rightly say, when they are ready.