Why does the modern media keep using the phrase "speaks out about" when they just mean "talks about"?

"speak out" has an idea of raising a subject that is difficult and not usually discussed. Saying "speaks out" makes the discussion seem more dramatic, more of a courageous effort, more worthwhile to listen to.

It is an example of the use of language to create an atmosphere, to compel people to become interested when they might otherwise not be. Hyperbole. Most of the time, the "speaking out" is not what I would call speaking out. There is nothing that would normally be hidden, nothing courageous in the act, nothing except someone discussing a subject.

It is not much different from all those headlines that tell us about some "Hilarious" thing that happened, which is not hilarious at all. At minimum, the person calling the thing hilarious must have a very different idea of hilarity than the average person, but most of us realize that the hyperbole is done for purpose of sales (to generate interest in something which is actually mundane).

The reason is these phrases are not identical in meaning. Anyone who talks about something is expressing an opinion, but those who speak out about something are making of point of having their opinion known or heard when it was previously not expressed, acknowledged, or recognized,

To 'speak out about' something means to do so publicly, with an implication that it takes some courage, or at least deliberate resolution, to do so. Just saying that someone 'talks about' a thing doesn't carry any such implication.

Probably the same reason that reporters say they "reached out to" somebody instead of "we called him up to ask him why he was such an a'hole but he didn't answer."

There are always multiple ways to express the same idea.

They do it like that to make it seem more dramatic.