College essay on same topic as preferred major.
My son has written his common app essay on this prompt "Describe a topic, idea, or concept you find so engaging it makes you lose all track of time. Why does it captivate you? What or who do you turn to when you want to learn more?"
He is laser focused on pursuing physics, astrophysics/astronomy and his essay, which I think is wonderfully written, describes how he started getting curious about stars, planets, galaxies when he was in 3rd grade. It takes the reader through a journey about how he furthered that using various avenues and
As he has started applying for various colleges, we are finding that for a couple colleges the starting prompt's response ends up being on the same lines as his common app essay.
1) Describe three experiences and/or activities that have helped develop your passion for a possible career in a STEM field.
2) Students at Yale have plenty of time to explore their academic interests before committing to one or more major fields of study. Many students either modify their original academic direction or change their minds entirely. As of this moment, what academic areas seem to fit your interests or goals most comfortably?
Why do these areas appeal to you?
Will he be at a disadvantage because of this ? He cannot change the responses to these individual college prompts as they require focused response. Should he pick another prompt for his common app essay ?
It will be helpful to get guidance on this situation.
I would not say that he is disadvantaged in total (for I have not read the essays), but I would say that he has given a very limited, a very narrow depiction of his “interests” as a person. Take, for example,  a student who wrote the supplement college prompts about his interests (which is a requirement as you have stated), and then wrote the common app essay on something completely different—like maybe how the student invested time into arts and crafts (small event) or organized a local blood drive for the community (big event). Meanwhile, take  a student who wrote both, or all, college essays about his/her single interests—STEM you have stated. Now which student has given a great, holistic depiction of themselves?
The second student’s interests were very “limited” (a college may find this a bit hard to accept, like “Yale”), whereas the first student’s interests were defined on two or more fields (a college would probably love this).
So whether the essay is good or not (and I presume that it is), the underlying question to the student is if they believe they have painted the greatest image of themselves in the essay? “Are the college admissions offices going to go ‘ooh’ and ‘awe’?”
Also note that the common app essay you stated—“Describe a topic...learn more?”—doesn't have to be solely about his career interests. It could be something completely different! Or something very specific that has that “awe” factor. Read this essay, it’s truly extraordinary for this prompt along the similar lines of STEM: (https://blog.collegevine.com/common-app-essay-examples/#prompt6)
I hoped I helped out a bit!! I’m just a peer trying to get into a good college too <3