Many people rely on social proof to form opinions; therein lies the power of PR.
PR firms are not dishonest for they need good reputation with news outlets. But PR firms serve overworked reporters with selective truths.
The firms feed the same story to different publications at once. Readers see similar stories in multiple places and assume a new trend has come.
With trend stories, PR firms line up some experts to talk about the industry generally. At the end of the experts, lies the client pulling the strings.