I didn't say too late, I said too long. You too are allowed to have your opinion and if you think defense is such an insignificant part of the game, you can go watch Arena ball. If an NFL defense can't stop an offense from scoring a TD, then they deserve to lose. It sounds like you just wanted the Chargers to win or had Herbert in your FFL. It isn't unfair that they couldn't keep the Chiefs from driving 65 yards and scoring the TD. The Chargers had their own chance to drive into FG range at the end of the game and they couldn't do it.
So, on the last two drives they failed to win the game with a FG drive and then let KC drive it down the field on them. What would be unfair would be to give them ANOTHER chance.