Agreed. As an immigrant myself - I think this gets lots on both sides of politics. Everyone talks about how the country is being ruined - when really its got the most advantages relative to the rest of the world.
I think it depends on where you're comparing it to, and what you mean by the "rest of the world". Most of the rest of the world, by area or population, is very poor. But the US is not so special compared to the developed parts of Europe or East Asia or Canada, offering many of the same quality-of-life benefits with inferior social services and less participatory democracy.
It's not quite so easy. I was born and raised in Spain, and live and work in the US. I have plenty of family still there, and travel there often enough. Does Spain have significant advantages in social services? Sure! Politics are a little better there too. I also vastly prefer Spain's urbanism, where even small towns are far more alive than the largest, densest US metros. But that's not all there is to it.
I look at Spain's labor market and I see a country that is massively failing: Triple the unemployment rate. People out of college there, with good majors, that end up making far less than what they'd to at McDonalds in the US. Young adults can't afford housing either, but not because they have massive student debt, or high healthcare costs, or extreme housing prices, but because salaries are pretty sad. My brother does bioinformatics and has a Ph.D, and he'd make 4x what he does, today, doing the same job in the massive, booming metropolis that is... St Louis, Missouri. He lives with our retired mother, and they can barely make ends meet.
Ultimately the higher growth advantage for the US is long lasting too: If your GDP growth is 0.5% higher than your neighbor, every single year, compound interest makes the difference very stark after a few decades... and a place like Spain already starts 30% poorer.
So yes, I'd still argue that the US is ahead in many areas. The riskiest issue is the difficulty of reforms: Good luck reforming higher education or healthcare, even though other countries have working systems that are better. But even though all it takes to see the advantages of change is to look a little bit, progress seems very difficult, as there's just so much money and power on the line in keeping the status quo. But that might be the theme of the last couple of decades in all democracies: Unwillingness to reform in the face of dysfunction.
As a US citizen, resident of 34 years, born and raised in the UK, I applaud your analysis.
I'd also add that the US is a fabulous place to live if you make a solid income (say, 10-20% above median), but a pretty shitty place to live if you do not.