Back in 2000, there were also fewer people participating in socnets, much less using them for discussing tough topics. And the dark net as there is now was not yet.

Both are what has "robbed" if that is the accurate word, membership from GC and BC. (Notice that BC does NOT have either the pro-contact or the youth rights majorities and yet it too has seen its rate of new members fall dramatically -- to me that disproves your theory that it is the pro-contact thingy)

I think most of our potential new members are on facebook and youtube, mostly ogling girl (and boy) videos, too busy to discuss with you and me. And the rest are on the dark net, invisible from here.

As for why VP still gets new members, it may help that you are not banned by Google and Wikipedia. You will predictably argue that is itself a consequence of your anti contact position. But even if true, it is so not through the purported mechanism you originally proposed.