A 4-1 record in the NFL should not be scoffed at.
Yes, the way the Kansas City Chiefs earned their first loss of the season was frustrating, but it happens in the NFL. There is a reason only two teams have achieved a perfect regular-season record in the modern era. The losses in October can be useful to a contender if the team learns from them and avoids repeating the same mistakes.
The Chiefs just need to limit the losses to have a chance at home-field advantage in the postseason — and the schedule is not getting any easier in the foreseeable future.