I think it depends on whether one is talking about modern as in modernity or modern as in modernism. Big difference, really. Plain old modern, modernity - that is just as you say: the up-to-date way of doing things in the world, and in whatever sphere. But "modernism" was a movement in art, culture, philosophy, and psychology obsessed with modernity's impact, and with debate over the direction modernity should take, in disparate fields. As a particular school of art and culture, it's about as "modern" as apple pie with a scoop of ice cream is a la mode. ("of the current fashion")
Modernism hit during a time when humankind was on a powerful upswing, in many ways. The Enlightenment had given a shiny new coat of varnish to science and rationality; religion's death grip on public policy had been significantly weakened, if not broken; monarchy's hegemonic hold was falling by the wayside left and right (to revolutions of better or worser sorts). Literacy and literature were ascendent. Even medicine was beginning to get a clue! Industrialism and technology were transforming the way we work, communicate and travel. Naturally, each of these little revolutions had its downsides (industrialism's came in for the biggest share of angst) - and so naturally modernism, obsessed as it was with modernity's impact, was a movement that embodied both an optimistic and a critical strain. Modernism had a particular morbid fascination with alienation, supposedly caused when beings who "naturally" are attuned to old ways and slow pace are suddenly plunged into our bewildering array of color, sound, speed and smoke.
Oh, alienation is real! To be sure. But the idea that modernity is the cause of it is idiotic, as should have been immediately apparent. These fools didn't read the ancient Greeks? Or Ovid? Augustine, for Christ's sake? No, they just wanted to gum their lips and go gaga over the trains and smokestacks and oh my god what's to become of us now that wool-stretchers are being thrown out of work by automatic wool-stretchers and wow how impressively modern and emo we all are, look how tall and squarish our buildings are.
Sometimes I think modernists invented nostalgia. But no, that's not at all true - nostalgia is a constant, just like alienation is. Human nature doesn't change. Particular, human attitudes towards change don't change. They just get clothed in new fads. Perhaps it would be better to say, modernists invented The Nostalgia Crisis.
In short, modernism is dated and quaint. Modernism's concerns seem incurably fusty to modern eyes. The stuff that modernism ballyhoo'd as spectacular advance seems now as ho as hum gets. We expect leaps of progress now, the way the olderns expected flowers in spring. The bad stuff that was decried back then, now seems either silly (much of the moral hand-wringing), or just a necessary cost that if we work hard enough, we can mitigate (pollution is an evergreen).
From the forgoing, modernism sounds a bit foolish, but harmless overall. Alas, it was not harmless. The real, enduring legacy of modernism was in art. Because modernism was not only obsessed with the impact of the new, and the clash of the old and new. In art and culture, modernist critics drove modernist creators to fetishize newness itself. Or more accurately: to fetishize novelty. Novelty of conception (novelty of art theoretical conception, as dictated and defined by art criticism) was enthroned, not merely as art's highest virtue, but as art's purpose. The plastic arts - painting, sculpture - had been pinnacles of culture! Their highest aims, nothing less than truth, beauty, the ennoblement of the human spirit! Modernism changed those virtues for a low, grubby goal: "We've seen this already. Show us something new."
Can it be believed that artists accepted this?
They EMBRACED it. They thought the trade looked great! Art critics offered artists legitimacy without fetters, and a smartsy, complicated explanation - anything the plebes didn't "get," it's their fault! The philistines. You just keep giving me new versions of art theory to write about, smartly, and I will make you look smart - and relevant. Art took that deal with both hands, and on clacked the shackles. Art was enslaved, made subordinate to art criticism.
Modernism is the moment when that happened. Modernism is when art crowned art criticism king, and was repaid in drudgery and blood sweat. Art criticism brutally whipped its subjects onward: "Show me something new! Your works that do not advance art critical theory mean nothing! Produce ever-more-meaningless, worthless works, just so long as some novel technique or conception is employed!"
Modernism's obsession with novelty has eaten art (and itself) alive. It's left a very interesting corpse, perhaps. For there were masterpieces produced along the way! Works of truth and beauty that did ennoble, even working within the oddball and utterly misconceived modernist constraint. The method may have been bankrupt, but there were masters at work in it: so masterpieces were inevitable. And each of those individual masterworks lives forever, as any truly great work of art is timeless and immortal. But at what cost, the method. Art itself, put at the disposal of novelty, made slave to criticism, has been first starved to death by modernism, then taxidermized, put on exhibit, and corpse-whipped - by postmodernism. Even the most idiotic and trivial new approaches and theories have been found out, and mined dry. Nothing to build on there. Not for artists who still remain convinced, hypnotized, that the only thing worth doing is to push some grubby little art critic's envelope for him.
After art critical theory exhausted modernism, postmodernism turned to criticism itself as the next form of art: art as the means of criticism. Art as commentary upon art, and upon modernism. Meta-art. This didn't take long to get stale, either.
Perhaps with first novelty and then snarkiness exhausted, truth and beauty may come back around? I'm not holding out much hope. People's faith in the new is inexhausted. Creators are busily working new media dry, and will remain convinced that novelty is the signal virtue of creativity until they finally tire of binding and cutting their feet and stunting their growth just to fit into shoes small enough to walk down the smaller and smaller avenues that remain "unexplored."
Anyway. I did and do like modernity. Modernity is as fresh and current today as today is!
Modernism, I've got a criticique of, around here someplace. If I ever get around to putting it down in definite form.
But tell us what you really think, dogimo!