Indeed. To add on to this, I think the amount of media that doesn’t exist far outweighs the amount of media that does exist. This includes things that exist in dreams For example, songs and movies you view and listen to in your dreams that your minds makes up, or, say, everything on this site and this one as well.
For example, a song from a genre that doesn’t exist yet, or a movie from a time period that also doesn’t exist. A song/movie/artwork/whatever with a mixture of '80s and '40s aesthetics. The list goes on and on. Actors and musicians that don’t exist in real life but do exist in dreams or alternate universes.
Speaking of alternate universes, if the multiverse does exist and the universe truly is large enough, there would be an alternate version of Star Wars out there, with the only difference being that Leia is blonde, or a version of Back to the Future where Eric Stoltz did get the part, or even a silent film version of Back to the Future made in the 1920s with Harold Lloyd as Marty. Universes where humans never evolved and say, the major civilizations and intelligent life form would be a bird or reptile of some kind.
I’d say 99% of all possibilities (including every possible song, movie, or TV show) doesn’t exist yet. And a good chunk of that never will exist… in this part of the universe.