IMOO, I think entertainment has certain seen a decline in quality in the last 10-20 years or so.
Music aside (yes, music's been pretty bad since the 90s), film and television has kind of teetered from the 90s till the mid-2000s or so, then it just dropped drastically. Many say SEINFELD was the last true great television series, and I kind of, only because even though I know a lot of shows since then have won a lot of critical praise, I personally dislike almost everything on TV today: THE OFFICE, MODERN FAMILY, GLEE, THE BIG BANG THEORY, etc... all of these shows are considered great TV, but I hate 'em. I find THE OFFICE to be extremely dull and boring, tremendous false advertising has confused the heck out of me about MODERN FAMILY (everybody makes it out to be a show about reverse-gendered polygomy, even though it isn't), the singing on GLEE is like fingernails on a blackboard (not to mention the creators swear the show is unique and different from other shows on TV, but it really isn't), and I hate how THE BIG BANG THEORY makes nerds seem like deranged sexually depraved weirdoes.
Another problem too is that Hollywood admittedly doesn't want to take a chance on anything new anymore. As far as TV goes, if one show turns out to be an unexpected hit, then all the networks have to copy it... I mean, how many mockumentary-style "sitcoms" do we have now because of THE OFFICE? And as far as movies go, this is exactly why the theaters are packed with remakes of past franchises that tarnish the originals because the movie industry is afraid of trying something new that may fail. Theaters are a joke today anyway... not only is it incredibly expensive to go see a movie in this day and age, but lately, the movie industry is slowly phasing out the theater experience altogether - they're trying to reserve theater space for this star-powered, big-budgeted, action movies, because apparently those are the ones they draw in the most money from theater goers.