The other issue is that I fundamentally don't think the problems of moderation and hosting are "separable" as the paper claims—the moderation of your content is intrinsic to the question of "who wants to be responsible for hosting and paying for this content?". And people are going to want to use moderation systems that make moderation decisions they agree with and support—they're not going to want to be paying for a hosting provider that hosts content they disagree with. That's why I see the fediverse "plurality of networks" federated model winning out in the end, because it can be funded and operated by small groups of people interoperating with each other rather then requiring large centralized directory resources that nobody wants to pay for.