It's tricky. If you look closer at turnovers, there's more nuance.
For any volume of passes, you're going to have x% intercepted. But what kind of interceptions?
What do we do where there is a miscommunication and the QB throws it right to the defender, since the WR made a poor read?
What about a pass tipped at the line that wobbles into a defender's hands? We may want to say that's a good defensive play, to get your hands up. But a defensive lineman only does that if his pass-rush was ineffective.
With that one, it makes me think about the idea that there can be no truly great 2nd basemen in baseball, as they're all just failed shortstops.
If your pass-rusher has more batted balls than sacks...he's not doing his job well.
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Other 'luck' potentials in football are ball-marking by the refs, penalties witnessed and called by refs, injuries (and not just 'injuries,' but who and at what point in the game, etc), quality of teams you play consecutively, weather conditions, and on and on.
I really think a big one that no one mentions is the ref's ball-marking on low-stakes, 2nd down plays in the first half. They're not being shitty with it or unethical, but please don't tell me they're being as careful then as they are on 4th and 1 plays in the 4th quarter, either.
So maybe teams have to punt 0.3 times more, on average, than they actually should have to. That's not nothing. But the game really is a game of inches and those inches add up here and there.