Data rights are for data about you and your behavior. If you retained copyright over all the data you produce by existing, you would be on the same level as companies today
I can see a possible future where actually purchasing a permanent, non-revocable access to some content will not be an option anymore. When you consider the practices that some of these companies have, of “vaulting” content or removing access to it due to cost or tax reasons, I am not so much in favor of laws that protect their IP or copyright anymore. At least, not unconditionally.
Your problem is much more aligned with right to repair rather than data ownership/privacy efforts.
It’s important that people know what they’re advocating for and understand the fundamentals of what the problem is. Confusing this problem with another problem only muddies the conversation and gets nothing done.
No one here is trying to outlaw Copyright, which is the mechanism that lets companies do as OP says; limit you from downloading their data.
Data sovereignty is not at all related to streaming movies or music and this comment confuses people who are curious to what the effort really is about.