Are you unfamiliar with poverty levels in America and how many people are affected by it? Lack of transportation, lack of libraries, lack of internet access are very real problems for students who live in poverty. It’s easy to say there’s X amount of public libraries, but can they reach them? If they cant, do they have internet at home? If they don’t, how do they use these free online resources? If they somehow get access to these resources, are they able to find a tutor if they need one or need help with these resources?
I'm quite familiar: as I said, I've spent the last decade working with students who are extremely low income on their journeys to medical school in some of the lowest resource places in the country (rural south, midwest and west).
Are there places where resources are an absolutely critical problem? Yes. But they are very few and far between (mostly places so rural that there is no cellular signal). Outside of that, many rural libraries have moved to having Wi-Fi hotspots available for checkout so people can come in every 2 weeks, check one out, and be able to access library (and other internet resources) remotely. That minimizes travel needed. There are even ways to get them if you can't physically go to the library- but the number of places where an adult can't physically get to a public library are, again, pretty few and far between: mostly localized to the far west and some areas of Appalachia.
If you have some specific citations / resources on what geographical spots in the US you're discussing and how those specific location based challenges impact taking the MCAT, I'm very interested to hear it.
But chances are, the impacts of SES on all other areas of the application are going to be far greater than impacts to the MCAT. It's much harder to get volunteer experience, clinical experience, research experience, in places so rural there is no library than it is to study for the MCAT.
As for cost if you can't access a library, you can find MCAT prep books on used bookstores (i.e., AbeBooks) for $5-$30 for a whole series pretty frequently, especially if you look for those that are a few years old. Anything since the 2016 revisions will work perfectly fine for the bulk of studying necessary, and even pre-2016 versions will work for a lot of material review.
And if someone is truly unable to access resources, they're likely eligible for the Fee Waiver program, which includes free prep materials as part of it, in addition to reduced exam fees.
And this is all assuming significant prep resources, outside of those freely available from AMCAS, are make- or-break for the MCAT. Presumably, anyone taking it will have textbooks and course notes from relevant content classes, and the free full length exam will allow someone to see how the exam is structured and how questions are phrased.
