Adverbs matter.
“‘great’ is not the superlative of ‘good’ (that, as a reminder, is ‘best’); I am not asking if the United States has had a positive impact on the world here (once again a deeply subjective question). Instead ‘greatness’ is about extent, amount, ability, or eminence: great means ‘very big’ not ‘very good.’ Thus Alexander, Catherine and Peter are all called ‘great’ but one may well argue if they were ‘good.’ And ‘exceptional’ also does not mean good; things can be exceptionally bad! The point of something being exceptional is merely that it is different in uncommon ways; to be ‘great’ is to be exceptional specifically in scale.”
https://acoup.blog/2022/07/08/collections-is-the-united-states-exceptional/