Agreed but is every relay operator going to spend the hours a day (at least ) to do that work? Forcing this into individual relay operators seems like something that will force centralisation more than giving relay operators the ability to subscribe to blocklists maintained by third parties whose job it is to create and maintain them. At first there will only be a few providers but people are very opinionated about how they want their content filtered (if at all) which will drive more competition and therefore decentralization around these block list providers.