This.
The other portion that's impossible to know from a rank list, but actually what 4th years really care about is how likely are they to match at their top choice. The uber-competitive person who matched into Internal Medicine at Wash U in St. Louis may stand out to you as an outsider, but how do you think that person feels if WUSTL was their 9th choice after Penn, Mass Gen, Hopkins, Duke, Northwestern, UCSF, Mayo, and UW in Seattle? What about the person who wanted to match derm but instead fell into a great Anesthesia program? A match list conveys nothing about context and is largely why it's so worthless.
Further, exceedingly few pre-meds are aware of which programs are actually top tier in their specialty. I guarantee that most wouldn't consider a peds match to Cincinnati Children's a very strong choice (I mean you can almost hear them roll their eyes "really, the University of Cincinnati?") and yet that's a top 5 peds program - better than the Duke's/Emory's/Stanford's of the world, at least when it comes to taking care of children (you could also argue that there are many other programs, at least in peds, better at producing generalists than CHOP, Boston Children's, Texas Children's, et al, which tend to draw/produce overwhelming numbers of those going on to fellowships. This is probably true in all specialties where if your goal is be a great clinician but not a subspecialist, going to a "top" program may be counterproductive). So that naivete about what programs are actually good across multiple specialties also contributes to the worthlessness of match lists.
Similarly, lots of people who could go to top academic places don't because that's simply not what they want to do. They may want to stay put because they have spouses and/or kids who they don't want to uproot. You don't know what the politics and competition to stay at a home program might have been that year (the biggest drama on my Match Day at my med school was which of the 14 women going into OB/GYN were going to get to stay - all 14 had significant reasons on why the home program was the best choice for them, but the program director had never filled more than 2 of his 4 spots with homegrown candidates...and yet to the outsider, those that got to stay likely would have been the least impressive matches even though they were the best candidates). There are simply way too many factors that go into a rank list for an applicant that you don't know when you only look at the end result in a very isolated setting.