Example: I knew literally nothing about any of the engineering disciplines until junior/senior year of highschool when a careers quiz directed me towards them.
Sure how many kids that are exposed to those do you think are going to start working towards being engineers when they are 5?
There is a big difference between finding an interest and then finding a career.
Nobody is saying guidance is bad. The point is when the guidance become constant. It's not about some innner genius, it's not even about finding what you are are good at. It's about finding the engine that will allow you to become good at something which is a combination between many factors including parents guidance.
But it's completely lacking when parent's start pushing the kids to try out may different things almost as chores.