I didn't mention it as an excuse, I mentioned it to give you, the clueless, some perspective. I stated that it would be a good game between the two teams, and I wasn't wrong. Despite missing a lot of their starters, the Chiefs still gave the defending champs a run for their money in their own house. There's no shame in that.
Now, the Chiefs were honorable when listing their injured as probable, and the probables ended up didn't play. Unlike their opponent... I know you don't know a lot about football, but yes, injuries at important positions is a real thing, and teams' successes or failures depend on their players to perform at their max quite a bit.
Losing one or two players is OK, and maybe someone will step up and perform. Losing important players at seemingly every position, that's a different story. I now feel that I have explain to you about the salary cap and roster limit, but why bothered...
Like I said, it's best if you just drop this conversation and go argue about something else that you have a clue in.