The 49ers have the second-most expensive backfield in the NFL behind the Saints.
The Saints spend big money on running backs because they have a mediocre quarterback -- Derek Carr. Just like the 49ers used to have a mediocre quarterback -- Jimmy Garoppolo. That's why the 49ers traded for Christian McCaffrey in the first place -- to work around Garoppolo's limitations.
When you have a mediocre quarterback, it makes sense to invest heavily in the run game and optimize that area of the offense, because the mediocre quarterback always will hold back the passing game no matter how many weapons he has and how good his pass protection is.
Brock Purdy is not a mediocre quarterback.
He's a Pro Bowl quarterback, an MVP candidate. A much, much better player than Garoppolo. Which means Purdy doesn't need one of the most expensive backfields in the NFL. He needs what any top-level quarterback benefits from: A good offensive line and receivers who get open.
The 49ers could trade Christian McCaffrey right now probably for a package that includes a first-round pick -- he just won the Offensive Player of the Year Award. And the 49ers still would have a great running game that features Elijah Mitchell, Jordan Mason and Deebo Samuel.
And with that first-round pick the 49ers acquire for McCaffrey, they could pick an offensive lineman or a tight end and improve their passing game. Because now that they have a Pro Bowl quarterback for the first time since Jeff Garcia, it's time to optimize the passing game. That's how teams win Super Bowls.
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