I tend to look at matchups first and foremost, but narratives exist too, and its as simple as this, the Chiefs season is over if they lose, and the Chargers are extremely banged up on offense, and riding high after beating the Eagles. I feel like Vegas feels the same based on the spread.
I think the KC defense makes life really hard for the Chargers offense. I don't see many holes in the run game opening, and I think even without McDuffie, the secondary can do enough to contain the Chargers pass catchers. Chargers OL is in shambles, and I think this is a game where Chris Jones just dominates.
For KC, I think Mahomes will be better than last week (and certainly better than Hurts last week) but not exactly great. I don't envision much rushing success (Barkley's was mostly just on a trick play) I also worry about LT UDFA Esa Pole getting his 1st start against Khalil Mack. One thing I find interesting, is Derwin James has played more of a "Joker" role this year, and hasn't been the "TE stopper" he's been in the past. I would expect Travis Kelce to have a bounce back game. Something like 6-70-1 feels reasonable. Kelce is quietly TE2 overall on the season, and I expect the Chargers defensive attention to be more on Rice.
Chiefs-24
Chargers-17