In his 2023 starts Retzlaff was a poor QB. Despite this, marginally better QB play has BYU in a bowl game. As I said at the time:
https://www.cougarboard.com/board/message.html?id=32096888
In 2024 Retzlaff has been a good, but not great QB. He's much improved and made a number of big plays. Despite this, marginally better QB play this year would have had BYU already in the CC game and a lock for at least an at-large CFP bid.