One of the book's major premises, as the parent mentioned, is journalists' dependence on cultivating sources. Yes, the media landscape has changed drastically - with journalists now have far few resources. If anything, this would make them more dependent on cultivated sources as well as corporate press releases and similar things.
Which is to say your argument is nothing but a vacuous "things are different" claim but the overall situation has to be "things are worse", which reinforces the book.
To me, like I said, mostly what I remember taking from it is how it got me thinking about how a journalists dependence on sources, and resource-constraints to be able to get out stories without exceeding available time to report em... leads to over-reliance on reporting what the powerful say as "the news" and by implication "what happened".
I'd suspect that is still relevant to the landscape of today, probably even MORE so because reporting resources have been so devastated, but do you think not?
Then where are all the labor and communist newspapers? Seems like nothing much has changed to me.
While it may be good work, it's so out of date it's useless as a tool for evaluating the media landscape of today.
I spent 20 years as a journalist and can tell you from first-hand experience and the contacts I have kept in the industry that the media today is not the same as the media of 2010, or 2000, or 1990, and certainly not the 1970's.