Why isn't prestige taken into account?

This is a misunderstanding of match process. There are 3 aspects to successfully matching into a medical residency. One you have to apply and be offered an interview. Two, how the residency program director (PD) ranks you post interview (ie are you the PD’s first choice, second choice, twentieth choice, not ranked (ouch)). Below is a survey of PDs that show the weight they give to various factors in deciding to offer an interview (fig.1) and two, in deciding where to rank an applicant (fig 2). To translate, Fig 1 shows that the factors that are most important to the PDs who replied are performance of applicant while in med school (graduating from a highly regarded med school was much less important). Fig 2 shows the that the factors that are most important to the PDs when deciding where to rank an applicant are interview performance combined with performance of applicant while in med school (graduating from a highly regarded med school was again much less important).

The third often overlooked aspect of matching (and perhaps most important) is a student’s rank list. The survey below shows the most important factor for applicants is geographical location (Fig 1). And when both PDs and students submit rank lists, a computer program decides where the applicant is matched AND the program is set up to favor the applicant’s rank list choices.

http://www.nrmp.org/main-residency-match-data/
http://www.nrmp.org/wp-content/uploads/2017/09/Applicant-Survey-Report-2017.pdf