It depends on what happens when I make more duplicates if it is a waste of resources. Suppose I want more Envoy armor but don't have the requisite items, but have plenty of the stuff needed to make more copies of WVW gear.
If I knew I would get more Legendary trunks it could well be worth it.
Another question is what happens if you have every legendary of a type already? The trunks don't do you much good unless new legendaries are added when there is a new expansion.
Inquiring minds want to know.