Glenn's correct of course, but I think Batya Ungar-Sargon's historical review is essential to understanding how this happened in the first place:

Ungar-Sargon points to three major trends driving the transformation of once socially eclectic mass media into today’s class-skewed press.
First, a “respectability counterrevolution” has stigmatized working-class culture as unworthy of media attention, pushing the urban press to cater to the tastes and interests of American sophisticates instead, as epitomized by The New Yorker.
Second, a “status revolution” has turned journalism, once a primarily middle-class profession, into an upper-class one, with aspiring writers and reporters from humble backgrounds having to scramble through a succession of apprenticeships just to get their first job.
Third, advertising has replaced subscriptions as the media’s main source of revenue, even as the industry consolidates into five major national conglomerates at the expense of a fast-disappearing local press.
Combined, these trends have meant that increasingly upscale journalists cater to equivalently upscale and liberal-minded readers, while the remaining few outlets addressing the working class become conservative outliers.

This actually undersells the shift. If you read older books like PG Wodehouse's Psmith, Journalist you'll see that even calling journalism a "middle-class profession" wasn't entirely accurate. It was aimed at the middle class, but its purveyors and practitioners tended to be on the lower end of that category, or even solidly lower-class. The "shoeleather reporter" certainly was.

Billy Windsor had started life twenty-five years before this story opens on his father's ranch in Wyoming. From there he had gone to a local paper of the type whose Society column consists of such items as "Pawnee Jim Williams was to town yesterday with a bunch of other cheap skates. We take this opportunity of once more informing Jim that he is a liar and a skunk," and whose editor works with a revolver on his desk and another in his hip-pocket.

Imagine telling Billy that one day it would be unremarkable for people in his profession to be paid 7-8 figures. He would've kicked you thoroughly for being a dirty liar.
And a skunk.