Of course not. Character is like anything else with kids, it is developed in part through experience. Activities are a critical part of developing various character traits.
I think the confusion is that by the time you are applying, you also need evidence of valued character traits, and that is indeed a tricky business.
But WAY too many people who generally grasp the concept of holistic review get this wrong. They basically think, “OK, from like grade 5 I will work on my academic qualifications and related achievements. Then when I am applying, I will try to satisfy the character stuff by doing a good job asking for recommendations and writing essays.”
And of course that sometimes works. And often does not. Because they didn’t take it seriously, they just viewed it as a check box thing they could clean up at the end with a little last-minute effort.
If they were instead taking it seriously, then like from grade 5 they would have been working on actually becoming a person of high character. And that involves actual time and effort all along.
And again, what you are saying to the kid who did that, who actually worked from grade 5 on becoming a person of high character, but that who doesn’t get into your hypothetical Harvard, is that they failed at being a kid because they didn’t have enough time left for enough gold stars, and they foolishly wasted time on things that developed character when there were so many more gold stars that they could have been pursuing instead.
And that may well be your values, but it isn’t Harvard’s.