Wow, that is a mindboggling omission. They didn't even try.
Interestingly, these archaeological trends correspond well with Jarom’s mention of the Nephites fortifying their cities and making weapons of war between 400–360 BC
However, the atlatl is believed to have been introduced to the Maya around 400 AD and the bow came later, very likely after BoM times. Also, the population in the Maya region did not abruptly decline at 400 BC, but continued to grow. The Maya "collapse" came about 500 years after the BoM collapse and happened slowly and non-uniformly over a couple of centuries, mostly due to gradual migration.
The illustrations in this article are of Aztec weaponry as observed by post-contact Europeans. Notice that one of the illustrations shows a copper axe head. That was a product of the Tarascans, neighbors of the Aztecs, and came about long after BoM times and was more of an elite status possession than a weapon - it was soft, unalloyed copper which is less effective and far more expensive and difficult to produce than a stone axe. The Maya did not smelt and did not use metal, even gold, until long after Moroni's time.
What surprised me was how this article makes a bizarre and abrupt change of direction about halfway through:
The Adversary is taking full advantage of the Internet in his efforts to tempt individuals and destroy testimonies. But the Internet can also be used to strengthen and fortify one’s faith. Not only are digital editions of the scriptures fully searchable and easily available on your tablet or smartphone, there is also a wealth of online resources provided by the Church and independent faithful organizations.
I find this very telling. The purpose of the article is to convince you that there is good archaeological support for the BoM but it gives up mid-stream and instead tries to convince you that researching on the internet can be a trap set by Satan. Apparently if you have the desire to continue learning after reading this article you are giving yourself over to the Prince of Darkness.
Do you need to resort to those kinds of tactics if you really believe you're presenting substantial evidence?