I think you might be underrating them. Sure Kliff thoroughly outcoached McCarthy in two matchups, and Vance was able to shut Dak down handily, but other teams haven't had as much luck. For instance, in the three times Gannon's defense has gone against Dak he has never held Dak under 40 points. Here are the scores.
41-21
51-26
40-34
But cowboys real strength is on defense. Dan Quin has turned them into a top 3 defense in the NFL.
The 41-21 and 51-26 games were in 2021 when the Eagles made the decision to build their offense first. And the 51-26 game was the season ending game when the Eagles had already clinched a playoff spot and sat almost EVERY starter including Hurts. The Cowboys played everyone and ran up the score.
In 2022, the 40-34 Dallas win was mainly because Hurts was out & Eagles had 4 turnovers that directly led to Dallas scores.
Either way, there wasn’t enough of a sample size where both Dak AND Hurts both played to draw any conclusions. The Eagles D did dominate the Cowboy offense in their first encounter of 2022, but Dak didn’t play in that game either.