People are also forgetting that someone who got into harvard medical school (or similar) with a 520 MCAT, 3.8+ GPA, tons of research, ECs, etc is MORE LIKELY to perform higher on Step 1 (Step 2 now) since this is likely someone who is more efficient --> more free time to strengthen their clinical skills (and these schools generally have great clinical training). These individuals ALREADY know how to pump out pubs and have UNLIMITED access to the top research in the world. These factors make these individuals much more attractive to residencies.
It's very rare that a low ranked MD (I attend a low-tier MD btw) or DO student will check all of the boxes above. Research is plentiful at my school but not many take advantage of it. Most of us can barely keep up with the material. On the other hand, I have friends at prestigious schools. Their matriculant age seems to be higher (Einstein is 26 for example) and generally have lots of "X" Factors on their applications as premeds (research, unique skills, etc) --> and this generally translates into more of the same accomplishments during med school.
If you were were betting $1000 and were asked to pick an individual with a 240+ step 1 + lots of pubs. You're given a pool of 50 students from Yale and 50 students from State School X. You're more likely to be right picking at random a student from yale. Yes, the state school might have 10/50 students who meet the criteria, but yale would have 40/50 students meet it. Since many students take Step 2 very late (right before or after ERAS), things like school prestige generally translate to "higher step 1, research, great clinical experience, unique skills"