There seems to be a pointed dearth of groundbreaking composers these days; at least, it's difficult to pinpoint those who are truly revolutionary and inspiring leaders of the art, since there's no longer a sense of celebrity attached to knowledgeable and skilled art music masters. Why is this?
I suspect the reasons are (at least) two-fold: First, we have been trapped by the 20th-Century movement, which has shackled "high art" -- already an outmoded concept, but still prevalent in today's mindset because of its natural origins in the psyche -- to a tradition that purposefully distanced itself from the tastes of the common ear, and all naturally-arising theories of consonance. This supposedly bold and intrepid and intellectually-inspired venture into the wilderness of atonality turned out only to be an elaborate and self-deluding parlor trick, fit for a panflash two bottles of Merlot into a dinner party, but unsuitable for wider consumption and appreciation by the ears of the general audience as well as the greater and secret chagrined angels of passionate musicians.
Sadly, musicians and composers aspire to impress by embracing (and truly enjoying, no doubt) a music that the greater public has no interest whatsoever in; those who choose to pursue otherwise tend to be those scoffed at as "pedestrian" by our overly-schooled and under-educated "professionals". This feeds directly into the second part of the problem, which is perpetuated by those aspiring composers leftover to pursue traditional harmonies.
Therefore, secondly, we can describe how our flirtation with Neoromanticism has nearly already been abandoned simply because the composers willing to dabble in it, however good their intentions may have been, simply lacked the common cultural familiarity and excitement with the style of harmony prevalent in the late Nineteenth Century, or they lacked the musicianship or fierce musical acuity necessary to write well for their chosen ensemble or instrument as well as the driven desire to learn.
So where are those who might be masters of this art? Off composing a safer and more freely expressive form of avant-garde music where rules do not apply! Or perhaps, they're seeking refuge in tone-rows and pretending their intellectualism will be recognized by an audience of living and breathing humans. In any case, they are far too intimidated by the great masters who have been elevated by the surging gilded platform of historical idolization to ever study their works in an attempt to emulate, duplicate, and surpass. Instead, musicologists do the shoe-shining work, but with the submissive aim of attempting to explain the mysteries of their genius analytically, without ever envisioning the goal of emulation, assimilation, and evolution. The dialectic motive is lost if we are content to describe our starting material without following the process through to its desired conclusion!
We have, as a whole, thrown in the towel on aesthetics and tried to create another version of our own, where we could hide behind the veil of highbrow criticism and the cerebral. How ironic that musicians -- artists of sound -- should sacrifice sonority altogether and instead play games with mathematical constructions! There is a similar argument to be made concerning the prevalence of computer-based notation's continued abuse as a compositional tool, but that's a digression to revisit another day.
There is incredibly good reason to pick up right were tonality left off -- and to incorporate the attempts of jazz music to do exactly that. But that is another story entirely, since it introduces the possibility of allowing Romantic idioms to die out and replacing them with cutting-edge exploration.
I due caveat: I don't wish to issue a call to arms and a restoration of century-old styles! Rather, our initiative must be to seize the technology that has allowed us to transmit all forms of music new and old, and begin creating works anew, without hesitating to reclaim what has been the art music community's most successful contributions to date. Let us not forget that the best composers of all time, as listed by music professionals and the public alike, fall by and large into a timeframe ending one hundred years ago.
UPDATE: The debate over "low art" and "high" art is probably one that continues at every step of the memetic evolution of art and culture; it's just that it tends to be forgotten over time, or has been obscured by legitimate social and economic constructs which hindered their initial definition in the first place. Nonetheless, the patrician's struggle to embrace the cultural movements initiated by the plebians is always a difficult one, but is even more so inevitable.