You mean like correcting the blatant errors in the grade school science texts?
This is exactly on point! Sure, having discussions and making students think deeper may affect their quiz/exam scores. However, there are countless examples of how these exams are no more than simulations of real life and how being able to respond to new situations creatively is the true measure of intelligence (sorry, I'm too lazy to bring any references but surely a Google search will reveal countless cases).
I now teach university undergraduate engineering classes after working in the industry for many years. What I now realize is that the people typically in this role have never worked as an Engineer and have NO CONTEXT to what they're actually teaching. With no context, how can these people be fair at assessment? In reality, either the product ships or it doesn't. But exams often become about solving some tricky problem that is from an 1800's analytical paper. Not to say these case studies aren't relevant, but the point is the objectives of education SHOULD BE some skill set as opposed to scoring high on some exam.
All that said, I believe the criteria used to make the conclusions in the summary are way off base and also lack context. Parents, don't stop debating with your children about what they're learning. People should balance questioning everything they are told with heuristics and best practices in order to "get things done." Test scores be damned if we can't even assemble lawn furniture at the end of the day.