Tbh I think the MCAT has been and continues to be the most important part of one's application.
I strongly disagree with this, as stated.
The most important part of ones application is your narrative on why you want to go into medicine coupled to a strong display of experiences (esp. clinical experience) that show you've demonstrated a commitment. MCAT is very, very far behind that in importance.
But, this thread opens up a lot of missing nuance around MCAT. I tell my students to consider it a "step" function. A particularly low MCAT score can absolutely keep you out of schools, just like a red flag on anything else: sub 3.0 GPA, missing clinical experience, not having any community service work, no narrative in your documents. But *increasing* your MCAT scores, for most schools, shows diminishing returns past roughly 60th percentile, at least for my students, compared to other uses of their time. Certainly some schools that care a lot about it.
Unlike SAT scores, the MCAT correlates well, and uniquely, to success in medical school. And more importantly, it correlates to standardized exams (STEP, for example) while college students don't have mandatory standardized steps at the end. As such, the ability to perform well on timed, standardized tests *is* an important facet of medical school admissions in a way it's not for college.
SAT scores have a really, really poor general correlation to success in college, especially success past 1st year GPA. When combined with HS GPA, it gets better, but both correlate strongly to income and zip code as well, and both income and zip code also correlate strongly with college success.
But I notice a lot of black or white discussions of MCAT scores here, when really they're an important piece of information that isn't the most important part of a medical school application, namely because MCAT scores only show whether you can succeed in medical school: they don't show what kind of a doctor you're going to become. For medical schools, having you not fail is important, but having graduates who go out to be successful doctors who meet the needs of their communities is far more important, and MCAT scores don't have any real bearing on those.
De-emphasizing MCAT scores, IMO, is a good approach. You need to know that a student has the academic background to be successful in medical school, and MCAT scores do a decent job of this, along with GPA. But they don't give the "rest" of the information that's super important to display.
The worries about the importance of ghost-written essays, for example, are something to consider, but it's rarely just the essay that has the impact: it's the essay in conjunction with the activities a student has actually done. In other words, it's not just about what you say but what you've *shown*.
As to writing essay prompts, one thing students should keep strongly in mind as they choose where they go for undergrad is the degree of support. I devote around 10-30 hours per applicant each Spring and Summer working with them on this, and we guarantee support to alumni for as many years as they need it after graduation. But also... the number of my advisees who skip taking a lot of humanities based writing classes find secondary prompts a lot harder, because they don't have the strong framework in this type of work that they could if they took a lot more humanities classes, especially those that are writing centered. Writing quickly and skillfully is something that can be developed, and there are a lot of ways to do it "free" during college by your class selections.