Interactive and group radio, with some limitations
Before I tell a story about an alternate development of radio, I would like to preface it. A number of (relatively) unchangeable realities impact any reinterpretation of radio's history. First, broadcasting is the natural application of one of radio's intrinsic "flaws." Waves go in every direction to everyone. We still struggle with this problem today, and a number of recent inventors have worked hard to overcome it. Second, the United States patent system encourages monopolies in the early stages of any technology. This is especially true in a case like radio where the technology depends on difficult physical inventions, like the vacuum tube. Third, broadcasting requires much more power than receiving. This is a natural limitation, evidenced in Inventing by the story about the amateur broadcaster tapping into streetcar power. Any alternate story has to acknowledge these built-in limitations.
Yet, radio clearly could have developed differently. For example, if the press had blamed Marconi instead of radio amateurs after the Titanic disaster, amateurs may have fared better in the first Radio Act. Consequently, their numbers may have grown before the war. If the war had not intervened, perhaps De Forest would have created an alternate system to cater to amateurs on the West Coast. A system designed around amateurs could have been interactive, with listeners transmitting feedback to the local broadcaster in near real-time.
What if amateurs had never discovered that crystals could detect radio waves? Individual amateurs could never have afforded to build their own sets, forcing them to work together. Perhaps towns would have constructed sets, like a barn raising. Imagine leaving your home to listen to a radio program with your neighbors.