Art in decadence?

[Belacqua]

I have been getting into paintings lately, and I am inclined to believe painters nowadays lack the mastery, elegance and symbolism of the masters of old, such as Vermeer.

Perhaps the same can be said about literature, with writers such as Dante still unmatched?

Is this a subjective perception, or can it be objectively proven?

A little bit of a detour here, but I think it's on topic overall....

The term "decadence" has a narrow meaning when applied to literature or painting, in addition to the broader meaning you're using here. For this more specific sense, decadence is what happens when the arts of a culture become playful and unserious and detach themselves from moral concerns. If a novelist writes a book with beautiful prose, about sensuous and provocative events, but without any sense of a moral conscience, this would be decadent. 

This definition was first applied to Latin literature of the late Roman Empire. Apuleius is decadent, while Cicero of Virgil are not. 

I've been working on all this lately because a novel-reading group I operate read Oscar Wilde's Picture of Dorian Gray. This was seen as scandalous and decadent in its time, because it is very much art-for-art's-sake, and we are invited to enjoy the main character's immoral pleasures. He comes to a bad end, but not before we can fantasize a life with unlimited time and money, spent entirely on pleasure. Wilde makes reference to J.K. Huysmans' book A Rebours, so I had the students read this too, as homework. This book is known as the Bible of decadence, since the main character spends his whole time indulging in various exquisite pleasures, some of which are harmful to those around him. Then we read Wilde's Salome, another example. And now we're reading Lolita, which is probably the most provocative of them all for modern people. As you know, Lolita is about a terrible pedophile, but the prose of the book is splendid and beautiful. It tests to the limit Wilde's assertion that books are neither moral nor immoral, only well written or badly written. Lolita is extremely well written, and its main character is extremely immoral. Of course he also comes to a bad end, but his evil career is described in detail with great wit and beauty. 

Now I think literature is swinging back again, away from Wilde's exclusive focus on beauty. Today many readers are morally too offended to read Lolita, and demand that a book or movie have a clear and uplifting moral message. So "political correctness," or #MeToo, or wokeness, or whatever the terms are, are changing the way people read -- or at least how people study literature in college. The Picture of Dorian Gray would require "trigger warnings" on nearly every page. (And for the record I am not against any of these things. Heightened awareness of harm or discrimination in society is good.) 

Anyway, the idea that art's main or only function is to evoke emotion is a product of Romantic-era values. Before those values became dominant, and apparently now that they are ending, the function was different at different times. What Wilde was fighting against in his own time was the prevalent idea that the function of art was moral uplift, edification, and making us into better people by example. It looks as though we are largely returning to these pre-Wilde values. 

As an example, I find nothing in recent Whitney Biennial exhibitions beautiful or elegant at all, but I find a great deal that is morally pure and intended to edify -- or maybe just preach and scold. It may be this shift in emphasis, in part, which is responsible for the change you point to -- mastery is no longer required if one shows one's moral purity.