Universities in the US and other countries are not the same, and comparing them is not really fruitful.
US universities do care about extracurriculars and GPA and other things because they aren’t optimizing for raw academic performance, they’re optimizing for various other things like an interesting student body (that attracts donors, professors, and future students), real-world networks, and so on.
No, that’s not even remotely close to what I wrote, at any level. In fact, it’s closer to the opposite, because selecting purely based on an abstract exam has nothing to do with being a real-world adult, whereas extracurriculars, internships, etc. do to some level.
US universities do care about extracurriculars and GPA and other things because they aren’t optimizing for raw academic performance, they’re optimizing for various other things like an interesting student body (that attracts donors, professors, and future students), real-world networks, and so on.