Exactly, all evidence suggests this could easily reduce user contributions by 50% or more. Why not instead do something that would actually increase intrinsic motivation? E.g. since IIRC people still retain copyright over the writing they publish, why not make it easier for people to turn that content into newspaper articles, blog posts, books, etc.
I'd be happy if I could just download all my comments. Right now it's restricted to the most recent 1000. I've been complaining about this to the admins for years and they keep saying they're working on it.