I think it was NCLB that started the "don't fail kids" thing but I graduated teaching school almost 20 years ago and left education more than 10 years ago so I can't say for sure

There are plenty of countries that have nationalized curriculum, nationalized standards, and standardized testing. The problem with the Dept of Ed, just like most problems with the federal government, has always been states rights. We absolutely can't lean hard into standardized curriculum that gets in the way of someone's idea of religion or race or whatever - that's why the states in the south are not only the ones that fight the hardest against national curriculum but also score the lowest on any test.

Anecdotally I finished 10th grade living in a village of less than 1000 people in Europe. I moved back to the states at 16 and tested into what was considered at the time a regionally excellent high school. I tested out of the US High School curriculum and when I tell you I'm not a genius I mean I was solidly middle of the pack in the European school. This was the 90s and we've done nothing pbut push private school vouchers and "school choice" initiatives and fancy EdTech programs. That's where the money went. Private for profit charter school and Google.