The point of the article is that courts are (sometimes) ignoring childrens' testimony and instead siding with unqualified experts who have a financial incentive to remove children from their preferred parent.
There are so, so many cases of children testifying against a parent while living under the care of another, then recanting years later as adults.
I don't have a good answer here because I think often the experts are unqualified and give bad advice, but it's important to acknowledge the depth of the problem
The issue is sometimes (maybe often) the children's testimony is in fact tainted and should be ignored. Here in the US there's actually a surprising number of high-profile historical cases that involve children being manipulated into false testimony, see for instance the McMartin preschool trial.