this is generally useful and true, but it was more so when boring and safe investments (e.g. government bonds) were paying significant interests.
As of now, a 10y US treasury bill will pay less than 2%, and 2% compounded is still not much ("your $1000 saved today will become $1999 if you don't touch it for 35 years!").
Learning to save in general is probably the more fundamental information, imho.
EDIT: obviously investing in stocks-based funds comes with extra risks, and extra profit. If anything learning that risk and profit are connected is an even more important insight.
There are places where you get 5-10% interests on fixed deposits (mostly Asian countries). At approx 7%, you can double your money in 10 years. At 10%, you can double in 7 years approx and so on. It all depends on where one is living, I suppose. I can't find anything in the US market though - bank interest rates are a joke, treasury/bond % is too low. Stock market is on fire, but most stocks are so expensive that it is out of reach for most Americans.
I am not sure what other choices Americans have ...
You shouldn't be comparing nominal returns between markets, what you should be comparing is the inflation adjusted real returns. That's why even if Japanese banks offer nearly no interest the currency is deflating and as a result holder might end up with a net profit
As of now, a 10y US treasury bill will pay less than 2%, and 2% compounded is still not much ("your $1000 saved today will become $1999 if you don't touch it for 35 years!").
Learning to save in general is probably the more fundamental information, imho.
EDIT: obviously investing in stocks-based funds comes with extra risks, and extra profit. If anything learning that risk and profit are connected is an even more important insight.