Back in 1984, when the Ensign published the first M2C articles, LDS intellectuals were still open to new ideas.
Now, though, they are so sure of themselves that they insist only their interpretations are correct and they aggressively fight new ideas. They even incorporate their dogmatic conclusions in their logo!*
They especially resist new ideas that corroborate the teachings of the prophets about Cumorah.
So did LDS leaders.
Joseph Fielding Smith specifically denounced it, pointing out that this theory would cause Latter-day Saints to become confused and disturbed in their faith in the Book of Mormon.**
Nevertheless, over the objections of LDS leaders (including members of the First Presidency speaking in General Conference), LDS scholars gradually accepted Hills' theory.
The BYU fantasy map at the left is a version of the CES map. They both teach LDS students to understand the Book of Mormon as taking place in a fantasy world.
The de-correlation of the teachings of the prophets about the New York Cumorah was a gradual process that took decades.
The game changer was probably John Sorenson's 1978 an Ancient American Setting for the Book of Mormon, David Palmer's 1981 book In Search of Cumorah, and the two M2C Ensign articles published in 1984.
In 1984 the FARMS newsletter titled Insights explained why their logo, now used by Book of Mormon Central, incorporates a Mayan glyph:
WHAT DOES THE F.A.R.M.S. LOGO STAND FOR? Many people have asked what the F.A.R.M.S. logo means. Here is a brief explanation. The logo is composed of characters from Hebrew, Creek, Mayan and Egyptian, which are four of the main ancient languages and cultures relevant to Book of Mormon reseach [sic]. The characters are set in four stone blocks, symbolizing archaeology and ancient reseach [sic].
"Within recent years there has arisen among certain students of the Book of Mormon a theory to the effect that within the period covered by the Book of Mormon, the Nephites and Lamanites were confined almost entirely within the borders of the territory comprising Central America and the southern portion of Mexico-the isthmus of Tehauntepec probably being the "narrow neck" of land spoken of in the Book of Mormon rather than the isthmus of Panama.
"This modernistic theory of necessity, in order to be consistent, must place the waters of Ripliancum and the Hill Cumorah some place within the restricted territory of Central America, notwithstanding the teachings of the Church to the contrary for upwards of 100 years. Because of this theory some members of the Church have become confused and greatly disturbed in their faith in the Book of Mormon. It is for this reason that evidence is here presented to show that it is not only possible that these places could be located as the Church has held during the past century, but that in very deed such is the case."