Picking up from where we left off...
(III) Admonishing his audience about "truth" and "shadows," Ruskin advises the artist not to let his passion for his creative endeavors and their results displace his interest and love for the subjects his art depicts—which Ruskin hopes to assume will be mountain scenes, meadows, marine vistas, and so on, or at the very least, real things in the world. If he ever countenanced the idea that the beloved objects an artist mirrors in her work might be images produced by other artists, he would have dismissed it toute de suite. Though he disliked Whistler's work enough to pen a scathing review, Ruskin probably wouldn't even condescend to comment on the CalArts style. (The joke's on him, of course: how many millions more people living right now care more about Adventure Time and Steven Universe than the Pre-Raphaelites or J.M.W. Turner?)
I don't suppose there's any feasible way of sifting through all the content uploaded to DeviantArt (it still exists!), Tumblr (ditto), Twitter, Instagram, etc. to determine how much more activity and enthusiasm surrounds "illustration" than, say, charcoal renders of models, studies of landscapes or urban structures, and other such efforts to represent real entities and places—but it's safe to say that an artist is far more likely to earn recognition and praise for producing and sharing She-Ra and the Princesses of Power fan content than pencil sketches of the objects sitting on her desk.
The artist sharing pictures of his in-universe Avatar: The Last Airbender or Sonic the Hedgehog OC is striving to imitate a style: I don't think we malign him in observing that he draws from art, not from life.¹ With a little introspection, we can easily infer the factors implicated in the young artist's being more inspired to draw what he fondly recognizes from a crisp, glowing screen than what he encounters in his day-to-day existence milling back and forth from rented home to alien workplace (or simply remaining at home) in the impersonal tristesse of our rudely mechanical century.
Much of the digital art I see adheres to one of a small number of predominant styles. From my vantage point, the CalArts look and its offshoots remain ubiquitous throughout webcomics, zines, and indie animation. Lately I've been seeing a lot material in a style that I can't put a name to (though its detractors identify it with "SJWs" and Tumblr); some of the concept art for the New Warriors reboot is a pretty good example. The influence of Invader Zim endures here and there, and the fursona avatars I occasionally encounter still have the "Disney's Robin Hood through beer goggles" vibe I remember from two decades ago.
But no contemporary illustration (or animation) style can compete with the distinctive look of anime and manga in terms of the sheer depth and breadth of its influence.
I hardly watch anime anymore; I don't follow any artists, and I'm not subscribed to any hashtags. But I see a lot of anime art by dint of friends' likes and retweets. Here are a few such images I scrolled past while drafting these posts: