The 2015 team deserves some flowers. That team didn't become elite defensively until down the stretch in Feb/March, and they also had some head scratching January losses, however the ACC was MUCH tougher then. As of today, I'd have this team ahead of the 2015 team, but not by much.
I'm not the type that bases how good/bad a Duke team is strictly off how far they made it in the tournament, that's dumb in a single elimination style format. For example, I think the 1999 Duke team is the best Duke team and maybe the best college basketball team ever assembled. 2002 and 2004 aren't far behind.
But the job isn't done yet for this team. They need to stay connected and stay committed on the defensive end while staying hungry. That 2015 team flipped the switch defensively, this team just needs to make sure the switch stays where it is.
Oh, and the Paolo team isn't anywhere close to this team. That team lost 82-67 in the ACC championship, had some head scratching losses throughout the season, and ended the year ranked #49 on Ken Pom D. NOT CLOSE. They made the final four but they were also down 5 to MSU with 3 minutes left in the 2nd round.