NOPE don't buy that average talent and a bad head coach will get you 8-8 in nearly any situation. Still doesn't fully make sense at all.
It does when you have a guy like Kyler running around out there like an MVP, as he did many times early in the season. Kyler gets injured, regression to the mean.
Kyler is a MASSIVE liability throwing the ball 10-18 yards down the field, which is the bread and butter range for nearly every offense. Teams began squatting the short zones and pressuring Kyler so he couldn't throw deep. That's one of the main reasons the Cardinals struggled down the stretch. So the concept that Kyler will drag this team isn't quite true at all, he was one of the main reasons the team struggled.
A MASSIVE liability? Maybe in 2019, but not in 2020. Since you brought the stat up, here's some more context around it:
"in Murray’s defense he did improve drastically from ‘19 to ‘20 when his PFF grade was 53.4 and in ‘20 it went up to 75.5 throwing in the 10-19 yard range."
Again, of all the things to hone in on for us struggling down the stretch, I didn't have Kyler in the intermediate as a major problem, but there are plenty of examples of scheme being an issue with this current staff. If you want to put it on Kyler, that's up to you.
This is the season to really judge Kliff.
You're right, who cares if we're the most penalized team in the league, or if we looked routinely confused, or if we're getting procedure penalties in EMPTY STADIUMS WITH NO NOISE. Let's just completely ignore the fact that this team had a gilded path to the playoffs last year and blew it.