I respect your view here but can't get on board with this line of thinking because the regular season is not a straight race to the summit. No-one cares about the Presidents' Trophy or achieving the maximum number of points. Instead there are two priorities - get enough points to qualify in a good position, and get the team in the best possible shape for the playoffs. The latter of these will usually mean basically voluntarily sacrificing points from time to time to manage minutes and injuries, develop tactics, and blood rookies, new trades etc. Furthermore, because seedings are determined by division and conference, not everyone is in exactly the same fight.
I don't want to undersell the regular season record. What the Bruins did last year was very impressive, and difficult to do. It was also a lot of fun. But I can never equate it with winning a Cup, let alone as surpassing it. If the NHL ran like one of the European soccer leagues - a simple fight to first place, with no finals - then I'd view it differently. Arsenal's unbeaten 2003-04 EPL season is rightly the stuff of legend. But in hockey the real war is fought in the postseason, where it's just the best teams, every game matters and everyone has the same goal. Lifting the Cup is all that truly matters, all that anyone actually remembers except when the record books are occasionally trotted out to make some point. Whereas regular season wins are simply a means to a largely separate end.
The other stumbling block to me in regards to appreciating the Bruins' record is that chasing the damn thing actually contributed to them losing in the first round. In that sense I see it as a bit of a tainted achievement - on balance I'm still glad they did it, because it was pretty remarkable and thoroughly enjoyable, but IMO there's also no denying it hurt them in the end when it came time to compete for the real goal. An example of great and sustained performance perhaps, but not greatness in its true and full sense.