I think the Patriots showed that there are ways to limit Mahomes and take away Kelce. If you can do that and play mistake free football (the Patriots did in the first half and didn't in the second) you can limit that offense. And yes the Chiefs will get defensive pieces back but they are still going to be vulnerable to most decent offenses. The Rams are loaded to the point where you have to pretty much play perfect and get some breaks to beat them.
Mahomes has 8 starts under his belt. 7 are this year. This league has shown time and time again that you shouldn't take early success of a young QB as predicative. Tape matters and the good teams are going to start analyzing this kid.
Also Andy Reid still has no concept of clock management and he's not going to cake walk through the playoffs without some tough games and someone smarter than him will exploit that. He already showed it by scoring too early against the Patriots in a situation everyone in the world saw as the set up for a clock killing field goal winning drive.
I buy the Rams far more. Goff is more tenured and is showing more maturity. They have the dynamic weapons in Gurley and Cook. They have strength on defense. They are just on fire.
Don't think the Packers have a shot this year. My bet is Patriots vs Chiefs and Saints vs Rams.