This isn’t exactly a Dark Age we’re going through. Yes, Twilight and Hannah Montana are everywhere, with their products manufactured for the masses with attention paid only to the bottom line, not talent or quality. But there are many, many artists out there and in the popular sphere who are creating new works with both skill and creativity.
Stephen Sondheim isn’t exactly Beethoven, nor is he even Richard Rogers or Oscar Hammerstein, but you can bet his contribution to music and the theatre will be remembered. Harold Pinter wasn’t Shakespeare, Haruki Murakami isn’t Dumas père, but even if their works aren’t placed in the Classics section in a few decades, someone else’s will be. Can you think of a time when all art was bad? Why should now be any different?
I’ve been using well-known examples, but you never know when a small-scale artist will have the spotlight shone on them. Furthermore, with such changes going on in the world such as technological advances and globalisation, there are many more artists around releasing extremely varied styles of work. Therefore a single figure is unlikely to rise above all the rest in their field for a significant amount of time.
Of course, tastes have changed and even though people are still composing classical music, it may not always make it to the stage. Operas and ballets these days do not usually adhere strictly to the conventions of past eras. The thing is, if they didn’t evolve, then I doubt they’d be remembered in 500 years at all.