CDDB(1) is a legacy way of quering for metadata, public service(s) have changed operators multiple times, some less concerned about privacy and there's no "easy" way to submit new data. It would be nice if support for CDDB were optional and not hardcoded to libcddb.
Reference:
https://hydrogenaud.io/index.php?PHPSESSID=029bfbfmciujgqp7o212mip5vd&topic=125880.0