Who would've guessed a few years ago that the 49ers made the wrong choice? Because without Harbaugh it sure seems like they made the wrong choice. Alex Smith has flourished while Kap is about to be traded.
Everyone knows the backstory. Alex was the 49ers starting quarterback when Kaepernick was drafted in 2011. By the 2012 season, Alex was established as the starting quarterback until a concussion made him a little less established. Kap took Smith's job and never gave it back after that concussion. The 49ers went onto the Super Bowl that year while the Chiefs traded for Alex a few months later.
It never did seem like there was a true rivalry between Alex and Kap, despite how hard the media tried to create one. Alex seemed to understand the business and how it works. Alex also isn't the type that's going to make their relationship a big thing. Kap hardly ever says anything so I suspect any Alex vs. Kap talk will be from the media and not them.
The two sides have played each other once since Alex was a Chief. Kap's 49ers beat the Chiefs in the 2014 season.