Personal statement
Volunteering
Extra curricular activities
Letters of recommendation
Dean's letter
Awards
Research
Presentations
Patient experience
Audition rotations/Sub I's
Out of 15+ interviews, I was asked one time about my board scores. The list above is what I was asked about. I tailored my application specifically to the field I applied to, and received numerous positive comments about my application package.
First off, congratulation, in all seriousness.
To comment though: of course they're not going to ask about board scores much at interviews, it's just a number listed on your application. There's not much else to know. But you can bet they used that number to decide whether you should even get that interview or not. So it got your foot in the door. The rest shows you had the time and made the effort to have well-rounded experiences.
However, not everyone is in the position to do all these things. Some people need more time to attend to family, or take longer to study, or aren't really as keen on the research/academic side of the profession, or aren't provided with quality opportunities by their school/area. Many of these activities are linked to privilege as well. Also, from experience at my own school and from other peoples' attestations, lots of the "volunteering", "research", and "extra-curriculars" people do have very little true value and are done as resume fillers. I'm not at all saying that's true of you, or of everyone, but it's definitely highly prevalent. It's just like all the filler stuff people list on their MCAT from undergrad. In summary, these are great things to have on top of test scores to talk about in interviews and add personality to the application, but in and of themselves should not be the basis for screening for residency interviews; that should be left to scores (like Step 1 and 2) in the context of the rest of the app.
Cramming lots of minutiae isn't ideal nor is it predictive of the type of physician one will make; however, it is indicative of the effort and ability someone put into learning the material and foundational knowledge (i.e. the type of student one is and could potentially be in a residency program). That's primarily why we go to school: to acquire knowledge of the subject matter and learn the skills that we will use in our field. Not to volunteer, do research, or participate in some club, which is all great but is secondary stuff to actually learning the foundational knowledge.
In summary, Step 1 wasn't the best way to stratify people, but it was an important way (in combination with Step 2) and a much better way than subjective (and often embellished) volunteering/research/etc. experiences. No, Step 1 doesn't predict how one will be as a physician, but it shouldn't have to. It works to signify to residencies how much time and effort one was willing to put into being a student of the profession and a life-long learner.