I can find some ranking metric that your country will be low on the list, I guarantee it. On the other hand, what metric can I find that puts it at #1? There are a few of those that work for the US.
sure, if you're looking for "any" ranking... but this is not some random dude's "top 100 countries to visit" or something. It's the U.N.'s official list of developed countries. That puts some credibility to it, and it is definitely relevant in this topic since people were discussing whether the US counted as developed country or not. That is certainly more credible than finding "some list where [my] country is low on". I'm sure they are out there but I don't think you can find any list by the UN or any other credible world-wide organization.
Please, feel free to prove me wrong!
Oh, and what list(s) did you have in mind where the US is #1? I can't think of many (at least not positive ones)