If the US leads the free world why isn't the legal age 18yr on most parts of the planet?

A few days ago I was reading a thread which I can’t find now, where the age of consent was brought up, and someone mentioned that where they were the age of consent was 16yrs. Here in the US society outwardly—seem to have a problem with the age of consent or how females should be considered until they reach it. Outwardly (—I guess because Hollywood is in California) no one is suppose to look at a 16 or 17yr old with any arouses whatsoever even if she physically has the body of a 19yr old (even thought the big secret is the age of consent in about half the US states _is 16yr_), she has to have no sex appeal to any male until one minute past midnight on the morning of her 18th birthday then like a bulb that is switched on she can be seen as sexy. Anyone who would see her as sexy or get aroused before that minute pass midnight is some sleazy perv.

About have of the world, and not the 3rd world has an age of consent that is 16yr, and most of Europe it is 15yr to 14yr. Would the US take the official stand to call those nations out as ”Perv Nations” (officially it is believed here than anyone looking at anyone under 18 has to be strange if not dangerous)because they have their age of consent lower than de facto legal age here of 18yr? Do you suppose their age of consent is lower because their young people mature earlier or they better at handling and managing sex than US minors who have to be controlled or at least guarded until 18?