https://ssi.armywarcollege.edu/pdffiles/PUB638.pdf
Great article on the Mexican armed forces and how they have evolved over time - lots of details that are useful for the game
couple of outtakes that shows the difference between today's Mexican Army and the Army at the time of V1 and V2.2
So yes is the Mexican Army of 2018 what ArmySgt described it as? The answer is yes
Was it that Army in 1997-98 at the time of the invasion in the V1 and V2.2 timeline - the answer is no
"The 1994 Zapatista uprising had two effects on the Mexican
military, principally the Army, that persist to this day. First, it served
as a wakeup call for a proud institution that found itself held at bay
by a group of lightly armed peasants, which brought international
scrutiny upon the country and its security policies and forces.
Second, it provided sound justification for additional funding for
modernization. This was quickly recognized and taken advantage
of by the military hierarchy. In addition to significant equipment
purchases, the institution embarked upon a thorough review of
its professional development of the officer corps, as well as of its
training and organization."
secondly
"The senior leadership of the armed forces recognized that
perpetuation of the status quo was not enough to ensure the forces’
utility in the future, and that a far more focused approach was needed.
Over the period of 10 years, massive improvements to barracks and
training facilities have been made throughout the country, and new
courses for Special Forces and the Army in low intensity warfare
developed. The most significant changes have, however, been in the
field of professional development for officers. Schools and courses
were developed for all rank levels, with successful completion being
a prerequisite for advancement. There is a course for captains, a
course for majors and lieutenant colonels, and a senior course for
colonels and brigadiers, all based at least in part on the American
equivalents. "