I don't agree that this should be viewed as a "season is over" thing and look to the future. Development is nice for sure, and a good benefit. But strictly focusing on this season, there was still a case to be made about giving another player a shot to see if they could get a boost in production. Lowest of the lows and it flat out hasn't been happening either at all, or not even close to consistently. Example? Patrick Mahomes just threw for about 100 MORE yards in one single game than BYU's QB has thrown in all 8 first halves combined this year.
If you want to make a case for the present, you're still staring at a good reason to give someone else a shot. It happens. Houston put Greg Ward in. Some teams might be scared to because they're worried about who is next in line.. and some do anyway, like LSU. Yet BYU at the very least has a proven player who was above average. There's just no way you can look at the production and seriously claim that the thought of a change for a boost could hurt, knowing what is there.