The Internet is becoming more centralized, more asymmetric in terms of information and power distribution, more biased, less secure and less trustworthy. Blockchain technologies already allow the decentralized exchange of digital assets in a secure and fair manner, but its application to information transmission is mostly unexplored. This article outlines our vision for ONTOCHAIN, a semantically enhanced blockchain software ecosystem that enables the creation of secure distributed applications that empower users, ensure their privacy, high quality of service, and ultimately encourage pluralism and democracy. The primary goal of ONTOCHAIN is to achieve trustworthy service exchange and content handling for a variety of disciplines, including health, economy, public services, energy and sustainability, news, media, entertainment, industry 4.0, and tourism, employing advanced knowledge management mechanisms.