BYU isn't strictly an academic institution. It serves as a vehicle to educate and spiritually strengthen the individuals who attend. By doing so, it hopes to strengthen the church as a whole. Hence "Enter to Learn, Go Forth to Serve". When we consider BYU's mission, we often only take into consideration the first half of that sentence. BYU is increasingly more concerned with the second half.
Having served on campus, many (of course not all) of the most academically meriting students are increasingly incapable of fulfilling the other half of this mission.
For those of you struggling with why you didn't get in, I feel for you because it's an amazing experience. Prove BYU admissions is wrong, and do what it takes to get there.