The Bruins model is based around sustaining a long-term competitive team that will almost always be a playoff contender and ideally a participant. Of course the Jacobs' want another Cup, but their number 1 priority is and for a long time has been maintaining a team that will keep the fans coming through the gates and watching on TV, and retain the Bruins' place within the New England sporting/media landscape.
That's why they've never given this core as much support as they could have, because they refused to stake too much of the team's future on improving chances of short-term success. Sweeney and Neely have naturally had a remit to try and make the team better, and take calculated risks within set limits, but they've never been allowed to give up or risk too much, to in effect go 'all in' to land the big trophy.
As a strategy it makes economic sense and as a fan it's not entirely reprehensible either, as it is nice to support a team that is a perennial contender and which most of the time is good to watch. But it's also frustrating as you can see guys like Bergeron having their final years being wasted away when they deserved better support and reward for all their efforts and sacrifices, and you felt that another Cup was within reach (and just maybe still is) with a little more boldness in team building and management.
But it's also that strategy that makes me quite sure that there's no way that the team will go for a full rebuild based on a crash and burn, at least not yet. It would make a nonsense of their team management in the last 5 years and make the drawbacks of that strategy even more frustrating. I expect changes to address existing deficiencies, and I hope Sweeney is finally able and willing to be more ambitious this off-season, but I don't see them going for a significant modification of the team's core components. That will only happen if and when they feel they can do it without damaging the team's competitiveness for more than 12 months, or when things have become so bad that they may as well bite the bullet and go for a wholesale rebuild rather than linger in mediocrity.