Legally-mandated Content Interoperability?

Apple’s closed system for music sales is under attack from French lawmakers. It may seem ironic that the country that invented central planning is leading the charge for the bazaar over the cathedral, but this has major implications for closed end-end systems across multiple domains, including ePublishing. Especially if other jurisdictions were to follow the French example, mandated DRM interoperability could lead to increased consumer choice and the end of “walled garden” content distribution systems.
On the other hand, scads of current business models, ranging from mobile phones to sat radio to TiVo, are based on subsidizing sales of hardware devices tied to particular services. If legally-mandated content interoperability were to eliminate such business models, might consumers actually suffer, because few new services get built, or because usability is weakened by lack of compelling end-end solutions?
I personally believe that consumers would probably benefit overall. There is a brisk business in both devices and services built around Windows Media Audio which, while proprietary, is interoperable. The Internet, mobile voice & SMS are all built around interoperability and (uncoincidentally) have grown at immense rates.
iMode revolutionized mobile data because it adopted the Internet model, where anyone could create content sites, rather than the WAP model of an operator-controlled content portal. In general if you create an ecosystem that lets innovation and competition happen on both ends – device and services – you will evolve much faster. A competitive market may generate less elegant solutions (viz. Windows PCs vs. Macs, and the human appendix) but that is more than made up for by the network effects.