What does "required to listen to feedback" mean? Sure, anyone can post to the mailing list, but my experience with the CSS mailing list (www-style) is that it can take months to get a reply, and the eventual reply can still be "we've decided not to address this" without giving any reason. There's a w3c policy document that says that this "should" not happen; yet happen it does.
While it's true that the CSS 2.1 specification is published on the web, it's also true that the published specification contains contradictions and does not contain enough information to pass the test suite.
Yes, it's like an open-source project: no-one's under any obligation to address the bug reports you file.