I completely disagree with you, quietly. I read a lot of adoption reports before adopting my dd, and there was only one case in which I questioned whether ss were giving up on the mum too soon, and whether she could parent her child with greater support.
In every other case, it wasn't just that this was a mum who was having temporary problems coping because of a drug addiction she could get help with. (There are women in that position, and I agree they shouldn't have their children taken off them.) No, these were women who led terrible, brutal, dysfunctional lives, who had never experienced adequate parenting themselves, who had failed all their other children, who displayed no understanding of what children need or empathy with children's feelings. Let me be really clear: women who use drugs do not necessarily end up like that, but women who have had brutal, dysfunctional lives do often end up on drugs, in order to anaesthetise their pain.
Children need at least one parent who is consistently loving and reliable and on their side. This need cannot be put on hold. Growing up in foster care while maintaining contact with the birth parent, hoping that one day she will be ready to parent, is a recipe for disaster. The child will be bewildered, confused about who is their parent, repeatedly distressed and disappointed by the birth parent. There is a poster on here called TheFirstMrsDeVere who can tell you about the impact of continued direct contact with a birth parent who cannot shape up to be a parent.
You will think that I have an axe to grind: I am an adoptive mother and I wouldn't have my child if she hadn't been taken away from her birth mother. But I am also a birth mother, and I do get how big a deal it is to take away children from their birth parents. I feel very, very sad for my dd and for her birth mother that they cannot be together. I hope that one day her birth mother will be able to get to a place where direct contact will be possible and beneficial for them both. But I also know that my dd needs parenting NOW. Her birth mother is not an evil woman - not by a very long stretch - but her problems are very long-standing and her other children (who stayed with her) are massively, irreversibly damaged in the most horrible ways. It is beyond naive to think that she can be supported to become a good enough mother in time for my dd.