It's a really bad stat for Dallas when you look at the bigger picture.
Washington and NY have been pretty awful since Prescott took over in 2016 and as a result, those 4 head-to-head games have given us a 3-1 "start" for our season. In the old 16 game format, it meant 7 wins and 5 losses from the 12 takes us to 10-6 which "looks" good but covers up the mediocrity.
We have either failed badly to capitalise on the 3-1 advantage or we just weren't that good.
Don't believe we've failed? Just look at the AFC East in the Brady years. All 3 East opponents were poor throughout (a few decent Jet teams aside) and it allowed the Patriots to garner easy wins. They picked up good (not always great) Ws outside their division which coupled with their 5ish in-division wins, landed playoffs constantly AND regular 1 seed.