Both Dallas coordinators are to blame.
The Cowboys should have made adjustments early, stacked the box with 10, and dared Goff to just drop back and beat them. Don't have to blitz. Everyone can drop out, but stack with 10, and then Mcvay would have eventually called more passing plays. The Cowboys were getting lit up on the ground, and the defense was STILL retreating at times at the snap, already 5 to 7 yards off the ball. Pitiful.
And Linehan? Well, he's ALWAYS outcoached, so we should have expected nothing less. Like the Rams, the Cowboys should have lived in play action passes, and Cooper would have had a HUGE day on PA passes, Gallup too. Instead, they just ran into 9-man boxes with the Rams SELLING OUT to stop the run. Dak should have thrown for 400+ yards, and 99% of them should have been on play action (just like Goff's yards).
Mcvay gets it. Wade Phillips gets it. And they outcoached our coordinators, and STILL only won by one score. Different Cowboy coaches and coordinators will produce different results.