Before the Internet things were different; this was the First Age.
If you wanted to get your message out there you needed either a lot of money, fame, or power. Usually you needed some combination of all three. Barring that you needed to find someone with money, fame, or power (or some combination) who was also willing to help you. These people were often elites of some kind. They could be professionals with an industry journal, the editor of a local magazine, a rich patron with connections, or even political party officials. These were the people who held the keys needed to pass into the public sphere: gatekeepers. Their job was to search out people of interest, people with something interesting to say, and promote them. Musicians needed talent scouts, authors needed agents, writers needed editors.
Attention was infinite and quality content was scarce. Gatekeepers filtered through the trash and surfaced the gems. The public paid attention because that was all that could be done.