There is more than one side to that story. Not to take away from your argument, but dupes are a sign of stagnation. A chasm between the new users (for whom it's not a dupe) and the old. A high dupe ratio will eventually drive away the older members.
The reason people complain about dupes is because for each of these forums, one can get attached to its evolution. You want to see it grow. Every time it surprises you: yay, it's still becoming better!
Dupes can mean the beginning of the end. Not to say it's a good reason to complain, but it is one. Don't tell the older members who've seen this site grow and want the best for it to "deal with it."
Anyway, upvoted because I'm not one of the older members and I've never seen this before :)
