The article is actually not literal regarding an M-16 vs an F-16. It's an anology showing the difference between a guerilla force with small weapons, against a larger well funded, well equipped force with superior firepower.

That being said though, any low flying tirbine aircraft is susceptible to small arms fire. You have to hit it in the compressor turbine, or discharge turbine to break at least one blade out, which should cause further "shelling" which breaks off the other blades. At 30,000 rpms, sh*t happens very quickly.