I agree with most of what you're saying. But the Falcons defense is playing significantly better than their season rankings. To get a sense of the level where they are playing now, just compare their numbers before/after their Week 11 bye:
Pre-bye (10 games)
- 28.3 points allowed
- 385.9 yards allowed
- 6.58 Pass Yd/Att
- 11 turnovers (1.1 per game)
Post-bye (8 games)
- 20.5 points allowed
- 344.5 yards allowed
- 6.13 Pass Yd/Att
- 15 turnovers (1.9 per game)
Since the Nov. 20 bye week and into the postseason, they have won seven of their last eight games, and allowed 21 or fewer points six of those eight outings. In that stretch of eight games, Atlanta has also forced 15 turnovers?—?four more than it managed over the first 10 weeks of the regular season. The post-bye 1.9 turnover rate would place them in the top-5 for the season had they maintained that pace all year, their yards allowed would put them in the top-16, and their points allowed per game would have them inside the top-12, above the league defensive average for 2016 (22.84 points allowed per game).
Also, from Week 1 to Week 9, the Falcons were 23rd in pass defense DVOA; but from that point on, they were 11th (ending at 19th on the season) and their defensive passer rating had fallen from nearly 101 to under 78.
The only area where they have regressed is their run defense (going from
4.16 Rush Yd/Att to 5.17!) Part of this may be due to sitting back in coverage more and taking away opposing passing games, which allows running backs to carve up short yardage easier.
But by the same token, New England has also outscored in opponents and protected late leads while playing prevent....but we are still ranked the #3 Run D