I’ve seen students who did the opposite of much of what I advise here yet still get accepted to a highly-selective college.
They spent more time grade-grubbing than they did learning. They did test prep like it was their job. They chose the activities they believed would be impressive on a resume, not necessarily those they enjoyed. They had incurable cases of namebranditis and applied to a long list of prestigious colleges without regard to fit (and were happy to attend whichever of those schools actually admitted them). They spent their high school years strategizing to satisfy a magic formula for admission.
But the fact that it worked for (a few of) them doesn’t mean it’s a good strategy for you.
There will always be students like those above who somehow get admitted to a college that denies most of its applicants. But in the pool of students who get acceptance letters from the most prestigious colleges, these kids in question are the outliers. You’re far more likely to find curious learners, kids who engaged in classroom discussion, kids who made an impact in activities they cared about, kids who gave standardized tests the attention they deserved without sacrificing inordinate time, money or sanity, and kids who were excited to keep learning and growing at a college that fit them, whichever one that might be.
If you’re contemplating duplicating the high school careers of older students based on their admissions results (not necessarily something I recommend, but still a common practice) emulate the type of students who are successful year after year. They’re happier, more excited about college, and likely to be successful during and after college. Don’t copy the outliers.