Due to its very nature, all formats of media are susceptible to external influence. It all depends on the location, time, and context of the production of a given piece of media. Therefore, there is no universal media system. The world is broken up into a multitude of media systems, each with influences that make them unique.
Depending on the type of country one may live in, their media systems could be drastically different. In nations with a tyrannical regime, the media often centers around supporting said regime, and covering up any opposition. Media creators are given little to no freedom with regards to content creation. However, in more democratic nations, media is varied and individualistic. Anyone can create almost anything they desire, with little regulation (unless contradicting with the law). However, this isn’t set in stone. Certain democratic nations can have restricted media systems, while certain tyrannical nations can have free media systems. However, the other way around is more common. While this concept is especially prevalent with news media, it can apply to other formats of media as well.
There is also the idea of originality in the media. Many believe that, due to the sheer amount of media in existence, all new media is no longer original. In other words, all media is influenced or inspired by older media in some way. This is especially prevalent in the film and television industries. However, this can also be exemplified through the style of news media in each individual media system.
Evidently, there are a multitude of external influences on media systems. However, these influences are not homogenous around the world. Each individual media system has its own external influences, unique from others. Therefore, no two media systems are exactly alike, due to said influences.