I certainly don't know the answer, and I find this explanation pretty unsatisfying, personally-- Admittedly I haven't paid attention to the PDO stat before this, but I would like someone who's watched these high PDO teams and watched the Canucks to clarify these results more in context so that they make sense and paint a clearer picture for me of what's actually happening.
Did Boston and New York ACTUALLY play a similar style as the Canucks currently do, where they seem to deliberately and consciously avoid peppering the net with shots (even though peppering as many shots as possible COULD be a better strategy, even for a highly skilled team)? Or are we just saying that they were highly skilled puck possession teams who were so skilled that you would expect them to get high PDOs? Because I don't think that's the same scenario (if that's really all that people are looking at, I'd consider their takes on what's happening pretty flawed).
If they DID play the same style (beyond just being highly skilled and having strong puck possession), however, WHY did they return back to a more normal number? What did people observe on the ice and in their games that became a visible problem of unsustainability? Did those high danger chances start to disappear, if so, why? Did they get just as many high danger chances/perfect play/open-net tip-ins, but they just inexplicably started to miss on them at a rate that matches teams that shoot on lower percentage chances? Did they become predictable and easy to plan around because their style of play was too fancy and hesitant? Is waiting for the perfect chance before shooting somehow too taxing, resulting in less effectiveness over time? What was the actual culprit?
What's working for the Canucks right now isn't really a matter of how much skill is present or whether a team has Jagrs or Lemieuxs, from what I've observed (although some baseline skill is obviously necessary to play the style they are), it's a matter of approach and play style, IMO. Dakota Joshua is playing the same way, and he's not really that skilled.
I'm open to the idea of what they're doing being unsustainable, or hell, even the possibility that they actually AREN'T a good team (your reassurance that they are means nothing to me-- my skepticism doesn't come from feeling offended on behalf of the team or something-- who cares about that?).
I'm just looking for a better argument than "The numbers continuing would be unprecedented/historic, ignoring all other factors leading to them, and there's no way they're as good as teams with more highly skilled guys (which again seems pretty irrelevant)".