This has been debunked so many times. Even if you take the data at face value, this statement cannot be backed up. https://www.weforum.org/agenda/2017/02/us-students-are-laggi...
Yes, we are behind a lot of countries. A lot of (VERY) small and (VERY) wealthy European countries for the most part, but also a handful of small Asian countries. But wait, we are ahead of Sweden in science? Is Sweden in the middle of some kind of crisis in their inability to educate their children? What about Norway and Denmark? What about Belgium and Austria and France? They all score about the same as the US in science, are they producing a "generation of dummy"?
What about this: https://jakubmarian.com/map-of-the-results-of-pisa-student-a...
If you don't just include the rich countries, Europe is doing terribly compared to the US. Of course when the US average is calculated, they don't just take the scores from the rich states separately.