I do not think current corporate MSM oulets have greater market share than the big networks did before cable and the internet.
I do not think any newspaper has greater market share than it did before TV news, cable news, and the internet.
Before when we had smaller local outlets, we got outlets with much greater variety in local coverage. Unless they were big enough to have someone stationed in Washington or the state house etc., they were going to be relying on others, like the AP, to get access to a lot of the facts and stories they needed.
Today I have access to way greater variety and depth in data, accuracy, and range of focus areas than any prior generation, any time I want. Most people don’t seem to want that - they want a single source, and choose the one they find most digestible.