That depends on what you compare it to. Plenty of first world countries are ahead of the US in many important aspects. But if you're setting the bar on the level of Russia or some third world countries, then yeah, it's pretty great.
- Unemployment rate and job openings
- Economic growth
- Disposable income
- Household income
- Low middle class tax rates
- GDP per capita
- Economic productivity
- Wealth creation opportunities
- Access to capital and investment
- Diversity (most competing first world nations are very homogeneous)
- Scale and variety of industry, the US is the #2 manufacturing nation for example
- Freedom of speech and ease of movement
- Tech infrastructure
- Best universities on earth
- By far the highest research & scientific output of any nation
- Leadership positions in: pharma, biotech, genetech, aerospace, software, Internet tech broadly, cloud, ecommerce, mobile, artificial intelligence, virtual reality, space / space tech, defense / military, agriculture, electric vehicles, nuclear and other energy fields, one of the leaders in solar, and numerous other fields
- America's median standard of living is still among the top dozen nations on earth
This is doubly so if you don't associate with the stereotypical American lifestyle of working 50 hours a week, 10 days vacation per year, and sending out work emails while holding your newborn baby.
Listing specific things is pointless – all these ratings are online anyway, but just to name a few:
- fucked up health care system
- gun violence rate higher than in most third world countries
- homicide rate worse than any other developed country, and worse than countries like Niger, Laos, India, or Iran
- those best universities will put you in a $200K+ debt hole that you'll spend a lifetime getting out of, and the mediocre universities are not cheap either (compared to almost free education in many developed countries)