[1]https://www.wsj.com/amp/articles/more-americans-are-renounci...
It gets even more complicated with capital gains or losses, and different rules for how losses can be moved between financial years.
(And if you live in the UAE that US passport will be really valuable if you need to avoid having you hand chopped off for pissing off the wrong people.)
take someone who makes a million+ dollars in california. Their marginal rate is 50% (37% federal + 13% CA, and with the note that the SALT limits due to Trump, dont really get them 37% back on the state tax anymore).
compare this to most european countries where your income tax rate at the top is 50% or less.
now, they have other taxes they pay (social and the like) outside of income taxes, but so does the US. FICA and ss fees also "taxes" in a way.
I agree with you they're not particularly low, though, especially when factoring in what you get or don't get. E.g. add health insurance into the picture and starts to look very different.
The US is pretty middle of the road in terms of tax.