I agree with this. Sometimes people understand "apply broadly" as "apply to every school whose 10-90 percentiles include your stats", but it's not quite like that. Like you said, there are state schools for which you need higher stats as an OOS. Plus, there are some mission-specific schools, and if you don't fit their mission, applying there is a waste of money and effort. Finally, just like you said, some people apply to too many reaches. I mean, does it make sense to apply to 10 or 15 top-20 schools with, like, an under 3.5 GPA and a MCAT of less than 34? Some people say: "But I have good ECs and I'm an all around awesome applicant, if it were not for my stats" - guess what? People who are competitive for top schools have high stats *and* awesome ECs.
Plus, I seriously doubt the quality of all the 53 applications. Everybody starts burning out at some point. I started burning out at about 15 applications, completed 17 and still have 4-7 to go.
If I sound a little bitter, that's because I am

I haven't heard anything for 20 days since I got my last interview (and I'm only going to 2 interviews so far, though to schools I'm very excited about), and it's really discouraging seeing people getting so many IIs while I'm just sitting there waiting. What's wrong with my application? I have good enough stats (3.96/4.0/38), and ECs (lots of published and presented medical research, clinical volunteering, serious leadership, teaching, mentoring etc, some hobbies), at least 3 of my 4 LORs are as strong as they can be and I have kind of an interesting personal story. Come on, where's the love?
🙁