The solution to this, at least in the case of Tor, is for existing sites (e.g., Wordpress, medium, etc…) to provide one-click onion-site publishing support.
I see it as a more of a chicken-and-egg issue. Publishers don’t come because there’s no audience, audience doesn’t come because there are no publishers. Plus, there is no recognition of distributed networks as a solution to censorship - the current non-enthusiast view of them ranges from “haven’t heard about it” through “tried it, found it useless” all the way to “it’s only for pedos and nazis”, which is extremely harmful for any meaningful and socially beneficial adoption, of course.
I’m not sure if those are the actual reasons. Certainly not a technical issue, though.