You are expecting too much. You want something like noise protocol (like Signal does for messages) but for files, plus guarantees of a blockchain. Ensuring dele

You are expecting too much. You want something like noise protocol (like Signal does for messages) but for files, plus guarantees of a blockchain. Ensuring deleted files are not kept is impossible. Use encryption containers such as Veracrypt, where all files is just a big binary blob, if you want that. Defining covered threat models would be useful, though.