The main issue is talent.
The average P5 school sends 2.7 players to the NFL via the draft each year. BYU sends 2.0 (since 1980), 1.2 (over the last 20 years) and 2.0 (over the last 5 years).
If the NFL draft is a reflection of overall talent - then we simply have less talent than the average P4 team. I think most of us who watch games know that.
And yes, I know coaches are responsible for talent - but overall Kalani is on the average (historically) and well above average (over the last 20 years) for a BYU coach
However, BYU is still significantly behind the P4 average. And yet some of you are surprised (and some of you are outraged) that the more we play P4 teams, the less wins we have.