So most of the complaints I have heard are about the Singapore Math style curriculum of Common Core for K-6. As I understand, these started being implemented in the US in the late 00-early 10s, with implementation increasing with time. So the set of ACT scores probably doesn’t reflect that change (first link). The second link is for 15 yo who would represent the guinea pigs kids of that change, with Singapore topping that list. The third link says that while the 15 yos haven’t improved the fourth and eighth graders have been vs the kids from 1995. So while it is too early to say that the new system is the cause for the improvement in the younger kids, I don’t think there is a reason to abandon it yet.
This really isn’t about wearing scarves and drinking Pinot Grigio while listening to Sigur Ros smelling you own farts while turning the future generations into Europhiles who hate America. It’s about implementing a program that has resulted in the Singapore kids being top ranked in math for the past two decades. Whether it will work with a significantly larger/diverse population remains to be seen, but there is reason to be optimistic.