Every season that McVay has been the HC of the Rams their offense hasn’t finished below 10th in the NFL in Total offense. This offense is built around deception and simplicity the rams use very few formations, but change the variations of those formations because this ensures that the defense is kept basic. This is less that Goff has to read and with the zone blocking scheme of the Rams Oline so that the boxes that they get which makes the calls and audibles limited and easy. Which helps them play fast and keep their eyes and steps the same.
You can limit the looks that DC’s can give you and alignments they can give according to limiting your formations. If you align in one play in a 2 X 2 formation and the next play you are in 3 X 1 is perfectly fine but it does change the read and gives the quarterback more for the quarterback to have to read and it gives the defense a better chance to disguise their coverages or blitzes. However, if you stay in a bunch formation or a variation of that almost every play you can be their is only certain things the defense can do.
So with less reads you have more of an ability to play faster and more aggressive. Also, the simplicity of their scheme makes it where the Line can become great at what they do as opposed to just being average at several schemes. Now the deception side of the Oline scheme is that McVay adds different line adjustments where he adds pulls, special kicks, or influence blocks. Couple that with the condensed formations and the WR’s can crack back and double down on ends or Outside Linebackers.