Your extracurriculars are ice breakers for interviews certainly, but "research" is a box that must be checked at a lot of competitive programs and especially in competitive fields. Yeah I didn't talk about my research either, because that's boring to discuss an interview. But the PDs do care. At the tippy top tier of programs, they gotta make cuts somewhere when there is an ocean of 260+ Steps and AOA candidates, and research is often a tiebreaker.
Also, there is a vast spectrum of what "extracurriculars" means and I should clarify. For med school, all that dumb shadowing, "clinical experience", clubs/leadership positions, and volunteering that people do to pad their resume...that crap ain't worth a thing for residency applications. But if you have legitimately interesting hobbies or are a normal human being, that is an asset in interviews and when the committees discuss your application. That should be a no-brainer. At the end of the day, though, you having an interest in brewing your own beer may make for a chill and engaging interview but it won't get you ranked to match if your Step 1 score is in the toilet.