@atomicpoet @fediversenews You're conflating a couple of different things:
Ownership of the content you create. You retain ownership of the content -- you can sell it to whomever you want.License to distribute the content, and the terms under which it can be distributed. You signed all of that away when you accepted reddit's Terms of Service.
Continued availability of your content, and your ability to move the content to another provider. They have an export facility, so you can do this. Maybe not easily (you only get your content, not all the content in a thread or a subreddit; getting into another system would depend on how closely their data model equals reddit's)The fediverse doesn't address point 1 or 2 at all -- those are the domain of the ToS for the particular Fediverse server you're on. It may not entirely address 3 either, since my understanding is that the server admin has to approve the migration of your account. If you want off of a server and onto another, it's possible that the server admin for the server you want off of could delay or prevent that. That a technical capability exists doesn't mean you'll be able to use it.
This isn't a technical problem, it's an intellectual property contract problem. Reddit, and all of the social media services, are built on their ability to use your IP however they want without crediting or paying you for it. Full stop. Here's the paragraph from the Reddit ToS (for non-EU). tl;dr: Reddit can do whatever they want with whatever you post on reddit, forever, and no takebacks. (Moral rights are basically what you're trying to assert in your post, and you already explicitly waived them.)
When Your Content is created with or submitted to the Services, you grant us a worldwide, royalty-free, perpetual, irrevocable, non-exclusive, transferable, and sublicensable license to use, copy, modify, adapt, prepare derivative works of, distribute, store, perform, and display Your Content and any name, username, voice, or likeness provided in connection with Your Content in all media formats and channels now known or later developed anywhere in the world. This license includes the right for us to make Your Content available for syndication, broadcast, distribution, or publication by other companies, organizations, or individuals who partner with Reddit. You also agree that we may remove metadata associated with Your Content, and you irrevocably waive any claims and assertions of moral rights or attribution with respect to Your Content.