Actually, it is both.
There is a wiping out of dissent media and a promotion and nationalization of favorable media.
Just to take it out of the usual suspects, Juan Peron is a perfect example of this. One of the first things Peron did in his rise to power was isolate the people from the media. He painted them as an enemy of the working class, something that belonged to the elites. He started censoring what could be shown, in the name of fairness and the truth he wanted to cover. In order to be part of the power structure, most of the media capitulated and became a cheerleader media.
At that, one would be hard pressed to find a dictator, especially one that rose via the waves of populism, that didn't rise this way. Parts of the press are always isolated and targeted as the enemy, that way the people can feel their information is not correct and they look to the leader, and him only, to provide the correct information. The dictator isolates the media not favorable and promotes the media that is.
Lather, rinse, repeat.
