We considered using another format like RDF as the basis for our system, in order to simplify this job for programmers by giving them more detailed information in an easily parsed format. However, our goal was to make this information accessible to human readers first, and machines second. Using well-structured HTML provided the best match with those priorities.
We are very interested to hear feedback and suggestions about other ways we might accomplish the same goals, while making the system more useful for webmasters, site visitors, or developers working on license-checking software. If we get enough suggestions to publish a new method that's noticeably improved over this one, we'll do so. (That's why this method uses such a verbose identifier for the license information table: to allow software to distinguish this method from others we might craft in the future.) If this is an issue that you're interested in, please subscribe to the LibreJS mailing list, and write there with your comments and suggestions. We look forward to hearing from you.