How low can LA Rams defense go and still make a SB run?

There is a belief that the LA Rams defense will not play to the same level of effectiveness as that of the 2020 defense (which was best in the NFL). But while that line of thinking has a bit of historic evidence to support that conclusion, the assertions have stopped with how low will the Rams defense regress. More importantly, how low can it go before improvements in other facets of the team are no longer able to compensate?

A recent article from Pro Football Focus Tim Riske, Defensive Regression and Offensive Question Marks: Why to be skeptical about the Los Angeles Rams in 2021, triggered a bit of contemplation about the LA Rams team. Both the offense and defense. It’s a persuasive article that blemishes the luster of the LA Rams optimism for 2021. The article takes two approaches to that argument. For starters, it argues that the Rams stout 2020 defense will falter in 2021. Why? Well, just because they do. The author argues that the Rams’ top-ranked defense was not as dominant as past top-ranked defenses, so the regression will be more renounced.

He states:

"“In general, no matter whether a defense loses players, the unit tends to regress the following season. The following chart shows the estimated distribution of results in the following year after a defense played a season as well as the Rams last year.” per PFF Timo Riske"

That’s a bit of a stretch. It’s the same argument that would cite last year’s injured player is more likely to be injured this year. There is actually no direct correlation. What happens is actually what I call a ‘new car’ effect.

If you purchase a new vehicle (doesn’t even need to be a current year model, just a car new to you), the presence of that vehicle on the streets for errands and commuting seems to rise significantly. It’s not that there are suddenly more cars like yours on the street. It’s that your awareness of that make, model, and year of that vehicle have risen, so you notice it on the street that much more frequently. In short, you’ve changed.  So the conclusion that the LA Rams defense will, through some unnamed force of entropy or NFL gravity, will normalize back to their normal state of being in 2021 is making an assertion that is, in effect, a circular reference.

It’s an analyst’s version of arguing: “Because I said so.” Nothing more. So what is the truth? What will happen to the LA Rams if the defense does regress?