I'm a lifelong Chiefs fan and pinch myself every day that this is happening in my lifetime! DH grew up in Colorado and is a Broncos fan. He's got zero skin in this, but has looked at all the numbers and watches all the games with me. Even he will tell you there's nothing to these allegations.
We've had this conversation a lot, and our theory is that replay has gotten better while officiating has not, so it seems like a lot more calls are wrong across the board, when it's likely about the same as it's always been.