I give it 12-24 months as a ballpark estimate before we're seriously short if action isn't taken. Maybe less -- the problem is only getting worse.
However our number are increaseing
Even if we manage break even in our supply of people willing to spend large swaths of time performing thankless tasks for no compensation, it's most definitely the wrong approach. Instead of building a large and expanding base of volunteers, we'd be struggling to maintain the status quo.
That fact is that most vanderlism is one off. You could lock down every major ISP and you still need people (ie the people you have just prevented from become part of the project) to watch recent changes.
Can you come up with a practical third?
Getting serious about blocking every opensource proxy we can find would be a favorit. More filters on recentchages would be another.