Have you ever seen "Network"?
The film explains exactly how and why this has happened, and it predicted today's sorry state of affairs right about the time things first started to go south in that industry. In a nutshell, TV news departments are no longer loss-leaders, operated as a proud public service for the sake of the broadcaster's reputation and prestige. They are now run by the Revenue Department, solely to raise advertising dollars, just like game shows and sitcoms. The news now tells people what they want to hear, or what the marketing execs THINK people want to hear, so more eyeballs will tune in and watch the commercials.