You could model after the pharmaceutical companies where
the drug gets a waiting period before generics can compete.
Use 12 months, Require downloadable files be zipped with a header that can be searched and automatically deleted.
You may think that's ridiculous, but things of that sort already exist. For example, there's a way to use DNS as a tunnel for other data. Yes, doing that is crazy.
If I'm incredibly pessimistic about this, it's because I've watched the long history of failure as many smart people attempted, then utterly failed, at doing this. One side must be perfect. The other needs just one opening. Games like that are so massively unfair that the only winning move is not to play. And you don't have to play: I've already pointed out how some artists have adapted and are doing good business. People want to support them. That's the way forward.
Maybe I'm wrong and someone will invent some magic technology that stops piracy. But anyone who is holding their breath waiting for it is very likely to suffocate. There are people looking for the way forward. It's just not a technical solution.