Brock Purdy has been viewed as Niners starting QB since February
Trey Lance wasn't traded to the Dallas Cowboys until just recently, but based on recent reports of Brock Purdy's rapid ascension in the San Francisco 49ers system, there was never much of a competition for the starting QB role in the Bay Area.
A deep dive from Matt Barrows at The Athletic looking into Purdy's resilience through a rib injury (subscription required) and his rise to become the QB that took the Niners all the way to the NFC Championship revealed that when head coach Kyle Shanahan watched all of his plays in February after the season, that's when he was convinced Purdy was his starting quarterback.
Though the Niners did their due dilligence and held an open tryout of sorts for the role between Purdy, Sam Darnold, and Lance, it was never much of a competition for the starting role: Purdy was the guy.
While the tape is what secured his role, it was the icing on top. Barrows' reporting dove into Purdy's playing through an injury and learning on the fly.