A lot of what I saw was more a lack of adjusting to motions/shifts surprisingly. Two high won’t be broken once they fix their motion adjustment.
They will also toy with more DL games potentially to push the gaps out but that does potentially come at the expense of pass rush
The kryptonite for defenses playing two high may have been found: two back formations.
Offenses used two back alignments on 14.3% of Week 1 plays, the NFL’s highest Week 1 rate in a decade.
Against coverages that kept the middle of the field open, those formations produced:
+0.10 EPA/play on runs (97 plays)
+0.26 EPA/play on passes (46 plays)
That rushing success extends beyond one week. Against coverages that kept the middle of the field open in 2025:
+0.06 EPA/play: Two back formations
+0.01 EPA/play: 2x2 formations
-0.01 EPA/play: 3x1 formations
With fullbacks, tight ends and additional running backs all capable of creating these looks, formations with two backs in the backfield could become an increasingly important answer to the league’s two high structures.