But the ledger is meaningless. You make 10 copies of a PNG and put them on a blockchain to sell them, nothing prevents me from making a million identical copies of that PNG and give them for free. It’s not even counterfeit. They’re the exact same item. NFTs aren’t even DRM.
Even if you wanted to keep track of who “owned” something, what does blockchain provide that a relational database doesn’t? Commit privileges on a GitHub repo have more real world impacts than who “owns” a no exclusive link to a URL (not even the domain or content hosted on the domain!), but that’s managed through an database.