The problem with those tv and movie databases are that they’re owned by Roku and you can’t download any data dumps…you’re also relying on the good graces of a corporation that can cut you off whenever it feels like it. That was the case with IMDb and I’m still upset about that :/
I think the only way to avoid a CDDB is to make the entire database downloadable so that someone, or a group of someones, is able to re-create it in case of disaster.
I think in the case of "great, open service" selling, the new buyer can just change the licensing, and you're out of luck. If there is a license that compels them to maintain some level of availability, you can trust them to cut it down to the absolute minimum, including rate limiting access down to a level of pointlessness.
