Why wouldn't it help IA? The specialist SEN legal firms still help some parents, even if they have to charge for it (and there is still legal aid for tribunal cases).
I know that Elaine Maxwell of Maxwell Gillot is a parent of an SEN child herself (and she says that's what motivated her to work in that area), and I know there are a few other SEN barristers/solicitors who have chosen to work in that area, because they either have dc with disabilities, or other family like siblings.