Analytics can be useful if used correctly as a tool. Coaches should not be making close to every decision based solely on what the numbers say. It does seem that the BYU coaching staff has relied too much on the numbers to make their decisions.
There is data that says that being extremely conservative on defense and limiting big plays forces the opposing offense to need more plays to score and that chances are they're going to make a mistake that prevents them from scoring if they have to sustain long drives. On paper that works which is why the numbers indicate it. But games aren't played on paper. Those numbers can't measure the emotional effect a 3rd down conversion has on both teams' players. Several 3rd conversions on the same drive could emotionally drain the defense to where their performance drops while the offense gains confidence and scores.