Alex -
Perhaps not all older materials are lost - this thread by 'Nootka' from 2012 still has the pics:
When I talked to Denis Dwyer May 25th, he mentioned that he could not find any info on Seymour Narrows on the site. In Sailing Directions BC volume one, there are diagrams of the Flood Stream and Ebb Stream showing whirlpools and best path (page 6-11, 17th edition). The photograph of Seymour...
westcoastpaddler.com
I picked that thread as I'd saved it in my computer, not confident it wouldn't be lost. Perhaps it's not representative of all the older posts.
Certainly many forums are full of 'broken' picture links - the worst offenders are forums that insisted on 'no picture uploads', instead having participants use picture hosting sites. Fortunately WCP has allowed uploads.