Not tough at all, good for Philly for doing what they had to do in FA and going and getting a franchise QB. They've earned this run.
No, the difference is in the coaching staff. You want to know how that is clearly evident. All you have to do is see how each team handled adversity in 2017...
The Eagles are 9-2 without Peters and Hicks and only have one loss minus
Carson Wentz. The Cowboys, however, cannot function without their left tackle or middle linebacker.
Tyron Smith did not play against Atlanta, in either game versus Philadelphia and was available for one series against Seattle.
Dallas lost three of those four games and put up a grand total of 34 points in those four games...
https://thelandryhat.com/2018/01/14/dallas-cowboys-coaching-staff-exposed-eagles-success/
Dallas Cowboys need to capitalize on Will McClay’s brilliance
...McClay has become one of the most sought after front office candidates in the league based on the work he has done with the Cowboys. Dallas has had a dramatic turn around in their offseason approach throughout the last decade. They used to be a team run by an owner who was not afraid to spend money and bring in the big name free agents only to see that decision blow up in their face both schematically and financially.
Just about every core player currently on the Cowboys has been brought in through the draft process without big money being wasted on has been free agents. This change in approach is not a coincidence with McClay being the man behind the scenes driving this change in philosophy. Since McClay has come to power within the organization, they are no longer afraid to let aging veterans walk in free agency or feel the need bring in big name free agents but instead, trust in the process in drafting and developing young core players.
Owner Jerry Jones certainly deserves his share of criticism throughout the years but his ability to retain McClay could perhaps be his biggest accomplishment in recent years. The Jones family has managed to build a sense of loyalty and belonging with McClay that has kept him around all while turning down chances to interview with teams offering him a new general manager title, which Jerry Jones will never forfeit...
https://thelandryhat.com/2018/01/14/dallas-cowboys-will-mcclay-brillance/
This is the point of destiny that Jerry and his chosen leadership, better not miss the opportunity and fail to improve application of today's NFL principals upon the field.
They better get good, or they may lose their functional GM and a window of opportunity as well.