The Age of Propaganda began with radio and peaked with four-network TV (CBS, ABC, NBC, PBS). The Age of Propaganda began to decline with birth of the The Age of Truth.
The Age of Truth began in late 1994 with the commercialization the Internet with the replacement of the NSFNet backbone with NAPs provided by MCI, MFS, Sprint, Pacific Bell, and Ameritech.
By the late 1990s, the rise of independent reporters began. In the 2000s, blogging platforms and media start-ups added to growth of the independent reporters and began weaken the establishment media as gatekeepers.
The appearance of Wikileaks and its publication of Iraq war-related facts further weakened the establishment media as gatekeepers. The revelations by Wikileaks during the 2016 US presidential campaign of collusion between establishment media, the Hillary Clinton campaign and the Democratic Party brought to an end the Age of Propaganda.
In a desperate last ploy, establishment media tried to call the upstarts "Fake News" but that only backfired.
Their latest ploy is "post-truth world." Those with power and their establishment media turned to their wordsmith propaganda outlet, Oxford Dictionaries. The editors there decreed post-truth as their word of the year. That too will fail.
We're now in the Age of Truth living among a Truth World.