This topic sounds like a good medical anthropology/public health thesis...
To get to the point though, I can see both sides' arguments, and I wonder, "Is there any ways (s) to make the journey towards becoming a doctor more efficient, yet not losing the high standards, the want of quality?" Because as noted, the world has varying educational systems that have been formed due to the history and progression of the peoples of that country, so it's hard to compare, because like someone noted, there are clearly competent physicians from other countries coming here to practice and teach, and I'm going to assume that they are competent because they excelled at acing the medical educational system their country offers, so what's the big hubbub?
The time commitment, financials, compromises...basically you need to situate your life to accommodate your medical education. It requires much preparation, dedication, and consistent effort over a long period of time to be successful, from your undergrad through the med school process to doing med school and the work that follows. For some people back in college, who wanted to be physicians, the idea of spending those many years, in debt if they didn't get scholarship/financial aid, and not even being assured they were going to get in even if they had a strong application, made them run the other way. Even the first Gen Chem course they took, after the first exam, many said, "Forget this. I'm majoring in ___." Because they realized, "If I can't ace Gen Chem now, how could I possibly do well in Orgo? Med school?" And for some who were on financial aid, the idea of not using the 4 years of undergrad to do something "useful" so to make money if not for their families, but themselves so their parents won't pay for them, made medicine less appealing. And to others, they simply just wanted to finish their prereqs for med school and their major by sophomore year, so either they had to do a science major, or a science major. For it's hard to do a humanities major and pre-reqs for med school in only two years.
Granted, some of them I do believe just need to hone their studying skills and be more confident, but at any rate, I get that the 8 year (and for some doing MD/PhD, MD/MPH, etc. , it's even longer) is a long haul. But it's the US medical system for now, and so far it has produced some great doctors (Atul Gawande, Benjamin Carson, Paul Farmer, Pardis Sabeti, Laurie Glimcher, to name a few), so one either bears with it, becomes powerful enough to change it, or go to another country. But I also understand that the medical school education could be condensed, considering again some of our counterparts overseas have such systems. And time does equate to money being invested, so I can also understand why one would want to shorten the academic journey of a doctor so to accommodate those who are in tough financial situations to the point that they might not be able to go to college, or enter a 4 year university, etc. Also, it could make the medical journey more accessible to underrepresented minorities, particularly Native Americans on reservations and those in rural areas that might not have the mentors, infrastructures, etc. that can get them through the process from start to finish.
Now for the liberal arts education. The college I'm talking about in the 3rd paragraph prides itself on its liberal arts education b/c it's a liberal arts college. There are plenty of discussions led by faculty on campus of the "disappearing" liberal arts education in this new age of STEM emphasis, and students arguing over if it's worth going into humanities b/c the liberal arts education makes the humanities so much more worthwhile, but "would I get a job with that?" All in all, I believe the liberal arts education is worth it. Now, I don't believe that means colleges should hike up their costs b/c they offer such an education, but at least for this college, the education is engaging, thought-provoking, and the professors (the ones who care about teaching and teach well, which a good portion do), make you think critically and discuss the ideas in class. Not saying it's "the" education or that it's perfect, but it suits well for those who want and are receptive to this education.