Yeah, I completely agree. There are already some services in this space trying to combat filter bubbles and walled gardens, Akasha [https://akasha.world/] for social networks, DNN Media [http://dnn.media/] for news and Lemon Email [https://ipfs.io/ipns/dapp.lemon.email/#/] (dApp and the full beta version) for email system. The last one is completely in line of what you're talking about. I like the approach through blockchain systems because, if used properly, they have the potential to become direction in favor of democratization and decentralization of information.