Framing this as a pattern across the entire industrial world is a bit misleading. Looking through the data at Math Scores since 2015 shows big country level split:
Japan: -3
S Korea: -1
Singapore: +1
Taiwan: +9
---
Germany: -45
France: -38
Sweden: -33
US: -10
This is an issue with the western industrialized world. Which ought to make the analysis simple since we can look at what those countries have done differently than their East Asian counterparts and stop pursing those actions as national policy
Japan: -3
S Korea: -1
Singapore: +1
Taiwan: +9
---
Germany: -45
France: -38
Sweden: -33
US: -10
This is an issue with the western industrialized world. Which ought to make the analysis simple since we can look at what those countries have done differently than their East Asian counterparts and stop pursing those actions as national policy
*edit for formatting