I did a search and this seems like pretty standard length of time for doctor training across all developed countries. However 1 major difference is, almost all other countries admit students directly into medical school after high school. Their med school is a year or two longer, but they don't have to do undergrad first before applying to med school. For example, to become a doctor in:
The UK (10-15 years):
After A level (HS, age 18), 5 years med school, 2 Foundation years (begin receiving stipend), 3 years general training, plus 1-5 years for specialty
France (9 to 11 years):
After Baccalaureate(HS, I think), 6 years med school (in last 3 years receive stipend), 3 years general medicine residency, plus 1-2 more for specialty.
Australia (11-14 years):
After HS, 5-6 years med school, 1 year intern, 1+ year resident, 4-6 years registrar(specialty)
Ireland (6-16 years):
After A level, 5 years med school, 1 year intern, 2-8 years specialty training
Japan (13 year-14 years):
After HS, 6 years med school, 2 years intern, 5-6 years specialty training
However, in developing countries where there's acute shortage of doctors, the training is much shorter, for e.g.
India (5 1/2 years):
4 1/2 years of med school, 1 year intern
So the real difference is 5-6 years of med school compared to our 8 (4 yrs undergrad+4 yrs med school). Also these other countries do not require their med school students and residents to do research. Their med school and residencies are primarily for hands on training, which allows them to shorten the time for both as proposed by this article.