So what's actually happening here -- not the specific topic, but the nature of the discussion?
[yes, it's my tired old 'opinions versus 
informed opinions' hobby-horse  

 ]
On the one hand, there is Group A: the majority of respondents, who are saying it's a bad thing that this information isn't common knowledge. A quick look at their profiles and posting history shows them to be older, more experienced members, which suggests that their opinions 
may be informed by more life experience -- having seen second- and third-order effects of applying diverse 'things learned.'  Now Group A may also be an example in dogmatic group-think, but because they've presented evidence to support their argument (in this case, lessons' learned plus the inherent benefits of knowing Canadian history to 'being' a Canadian), I'd  personally discount it; it needs to be considered when weighing arguments though.
Group B presently seems limited to 
Shipwreck and 
rinoakes -- from their profiles, two young sailors claiming there's little utility in knowing of things "old" -- who have stated little more than that they already know enough to be good at their jobs; they don't know about the topic, and in their opinion see no reason why they should care about it.  In effect, they appear to have no thirst for 'knowing'...for learning as broadly and deeply about a wide range of subjects, and how that can improve them as individuals.  
From their follow-on posts, it's not merely the absence of such a thirst for knowledge, there seems to be an active shunning of it.
....and 
that is what's sad about their not knowing of Vimy.
:not-again:  I'm done.