Willie would be wrong then. The Pats have always been worse in Defensive DVOA than PPG. The question is what you value more. Some people will argue PPG is more important because points win and lose games. Some people will say that attributing PPG to one side of the ball (especially defense) isn't the best assessment because the offense and special teams influence it too much (time of possession, field position, a lead can make the opposing offense play higher risk to chase points which helps the defense) and DVOA is a better metric to isolate the performance of the defense on it's own.
It's probably a mix of both, but it's not entirely wrong to say that outside of 2003, the common sentiment that the Patriots were a defense first team and the offense just played good enough, wasn't accurate.
We played in 9 SB's. In exactly 1 of them the defense was clearly the showcase unit of the team. In 2001 and 2004 they were pretty much even contributors (slightly more defense in 01, slightly more offense in 04). After, while the defense was always important, the offense was really the premier unit on the team. 07 was clearly offense even if the defense was very good. 2011 the offense carried a very bad defense to a Super Bowl. 2014, 2016, 2017 the offense was clearly one of the best units in the league, the defense was again solid, but the if the offense regressed to the defenses level we weren't really going to be competing for Super Bowls. 2018 is kinda tough because the offense was a better overall unit but the defense clicking towards the end is what really got the run started. Though they absolutely still needed the offense to get past the Chiefs when the defense collapsed, but you can say the defense returned the favor in the Super Bowl.