Single Males: I found data for this by county/age/year but it will take a little time for me to answer the question with a good graph. On my to-do list.
GDP per capita: The measure used for inequality is the Gini coefficient. The U.S. is around 40, while the countries you mentioned are around 30, where closer to 0 is more equality. So, our GDP per capita is higher while we still have plenty of poor due to inequality. Map with Gini coefficients and an explanation of what it means: https://worldpopulationreview.com/country-rankings/gini-coefficient-by-country.
Single Males: I found data for this by county/age/year but it will take a little time for me to answer the question with a good graph. On my to-do list.
GDP per capita: The measure used for inequality is the Gini coefficient. The U.S. is around 40, while the countries you mentioned are around 30, where closer to 0 is more equality. So, our GDP per capita is higher while we still have plenty of poor due to inequality. Map with Gini coefficients and an explanation of what it means: https://worldpopulationreview.com/country-rankings/gini-coefficient-by-country.