Why are those countries the exception and not America?
Other countries figure it out. America cannot. Therefore, it's not possible. America!
The poster you are responding to is probably incorrect in many regards. There aren't really 'exceptions' just 'differences'.
For example, Japan's economy definitely is not feeling good at the moment, even if some particular metrics are performing at a top tier.
We should not ignore that for countries like Japan and Germany, they have an enormous advantage in not having to spend realistically on a defense budget relative to their risk-prone geography, living as they do under an umbrella.
https://data.worldbank.org/indicator/MS.MIL.XPND.GD.ZS?end=2...
https://www.washingtonpost.com/news/worldviews/wp/2015/02/19...
Ironically, you can generally have your financial house in order as a country or be globally manufacturing-competitive, but not both*.
* Exceptions Germany, Japan, et al., but as you go up the value chain you gain enough profit leeway to paper over the general rule.