Report: The 49ers “flirted” with bringing in Steve Spagnuolo as defensive coordinator after the Super Bowl

The NFL is riddled with “what ifs.” You could make an interesting docuseries about the San Francisco 49ers under Kyle Shanahan about the moves they almost made or did but didn’t work out for various reasons.
DeForest Buckner. Jimmy Garoppolo’s ACL. Dee Ford. Trey Lance. And those are only four without delving deeper.
Dianna Russini of The Athletic recently stated on The Athletic’s podcast that the 49ers were flirting with the defensive coordinator responsible for their failure to win their sixth Lombardi Trophy:
“And on the coaching side, there is no cap, correct? Steve Spagnuolo signs a few days later. San Francisco flirted with him and brought him in as DC.”

I’d love to see the list of names Kyle Shanahan and the Niners considered. Spags, Bill Belichick, and Mike Vrabel. The list goes on. I am more interested in the “why.” What would be the motive for those names, or the others Shanahan cited, to decline the job offer?
Spags’ phone call could have been as simple as, “Thanks, but no thanks.”
I was convinced that the Niners would win the Super Bowl since, historically, good/great offenses outperformed good/great defenses. What I neglected to account for was Spags’ outstanding performance in high-pressure circumstances.

He is responsible for the Chiefs’ Super Bowl appearance and victory. DeMeco Ryans was, in my opinion, the finest defensive coordinator in 2022, but Spagnuolo took the title in 2023.
Shanahan may not get Spags, but he does have the opportunity to take away his closest assistant.