Every applicant writes some version of this: "I am excited about [School]'s world-class faculty, diverse student body, and collaborative culture. I look forward to taking Professor [Name]'s class on [Topic] and joining the [Club] to further my passion for [Industry]."

That essay could be about literally any top program. Swap the school name and the professor name and it works for five different applications. Admissions committees have read a thousand of these. They can tell when someone actually researched the program and when someone spent 20 minutes on the website and called it done.

The "why school" essay is not about why the school is great. The school already knows it's great. It's about why the school is great for you, specifically, given your goals, your story, and what you bring to the table.

That's a very different essay. And writing it well requires actual research, not just browsing the website.