Actually, my proposal goes beyond open consensus, because I consider blacklisting to potentially be too severe to allow it to be determined by a simple consensus decision (i.e. a single source of truth decided by general agreement).

My proposal is more of an "opt-in" strategy, where each user decides for himself which blacklists he wants a frontend to consider.

This is also the approach I want to take for future reputation/rating systems as well. In the reputation and rating system I'm envisioning, there will be no "single source of truth" decided by general consensus. Instead each individual will get to select whom they want to trust to provide them with reputation information, and they'll be able to weight the significance of those sources. So each user will get custom data based on their own choices.