Subjects taught at school haven't really changed – math, science, writing, a bit of philosophy and languages, i. e. the liberal arts curriculum. None of that is "useless" as it's more about learning-to-learn anyway.

And young people today are better than previous generations in basically any category: SATs have risen steadily, political participation is at the level of the late 60ies, volunteering is commonplace, crime is at an all-time low and cultural output is exploding.

The only thing that could ruin the next generation would be teaching them "pratical skills" by which people usually mean stuff like accounting. That's the humans-as-economic-units view that leads to exactly the situation in Japan: Millions of super-educated, completely generic young people who work 12h a day as told without ever complaining or having an original thought.