The idea is that people are born good, and are corrupted by society. Thus, children and teens are closer to original goodness, as they have not been corrupted as much yet.
This is exactly opposite of reality. Children are born as wild animals that need to be tamed and trained to fit into society and ordered liberty.
Relying on children for wisdom is insanity.
The deification of Greta Thunberg is a perfect example of your point.