I think that is a pretty large oversimplification. Wilson and co. are more familiar with San Fran than anybody. The 49ers DC was from Seattle, in addition to facing them twice a year. The Chiefs face them once every 4 years, I don't expect Mahomes to be as good as Wilson at knowing coverages or where blitzers are coming from. I'd also put the Seahawks WR's up against the Chiefs WR's and call that a draw, both speed wise and overall talent wise. Don't forget the Seahawks had Josh Gordon for their win over San Fran. Seattle also had a much better running game with Carson/Penny at the time.
On the other side, there is no reason the 49ers can't do the exact thing they have done the past 2 weeks on offense. Both the Packers, and especially the Vikings, have better defenses than the Chiefs do.
The Chiefs have a shot, but they have to get up early. If they fall into a 10+ point hole again, like they have the last 2 games, I don't think they can fight out of it, because they are going from facing mediocre defenses, to the very best one in the league. If KC can get up early, and make it so Garoppolo has to have a big game, the Chiefs can win, but that requires beating that D and shutting down that run game early, and I'm not confident they can do either, let alone both.