Generally, no, I don't think that serious = atonal and pabulum = tonal.
(I assume, of course, that we are talking about tonal music being composed
nowadays.) But somehow it happens that most neotonal works I heard sound
reused and recycled to me, as if tired of their own musical language.
Their composers seem to reach for musical devices that have become
cliches a long time ago.  I want something fresh and new, a new kind of
musical beauty, and I find it in, among others, Carter and Boulez.  Or
in Lutoslawski, whose works exhibit timbres and textures of breathtaking
beauty - this is best heard in the sections that are commonly called
"controlled aleatorism", although the composer preferred to call it
"rhythmic counterpoint", which is of course a much more suitable name.
His sense of timbre was uncanny, and by leaving the *exact* duration of
particular notes to the performers, he achieved extremely flexible, unusual
textures.  His music, as a matter of fact, was rooted to a large extent in
the French tradition, one of whose representative composers is exactly
Boulez - again a master of colors and textures -, another was Messiaen, and
which goes back to Debussy and other French composers (Chabrier, Chausson,
Duparc, Faure).  So here we have a continuity of a certain tradition, a
certain approach to music; that the musical language changes is inevitable:
how long can one repeat the same musical tricks??? But continuity is there,
and if it's not obvious at first listening, it will become obvious in due
course.  (Unless you just don't like this music - not everything is to
everybody's taste.)

It has always puzzled me why people juxtapose "modern" and "non-modern
(traditional?)" music.  The continuity of the Western musical tradition
is very strong; at no point can one say "here ends music and cacophony
starts".  Well, some did say that in the past, at various times:  the
accompanied monody of the early 17th C was cacophony to some
traditionalists used to the renaissance polyphony.  Ars Nova was cacophony
to some composers or theoreticians of Ars Antiqua.  Of course, Beethoven
was cacophony to some critics.  Liszt and Wagner were similarly derided.
What else is new? The Prix de Rome went on many occasions to composers who
should be glad if they became as much as footnotes to music history, while
Debussy had to try three times before he got it.  OK, this is getting
off-topic.

There are still genres in which tonal music has its place.  For instance,
the literary cabaret kind of songs still written and heard in Europe whose
tradition included works by Schoenberg or Weill, and later, Brassens or
Brel, for instance.  But that genre is as much literary as musical - it's
often a social commentary on our world.  There are certainly others which
just don't occur to me at the moment.

-Margaret Mikulska