I think Miyazaki has a definite point, BUT... Lets look back on anime throughout recent history (say, 30 years or so); how many of those titles really were superior, or in fact, were NOT unbearably eye-cancerish, brain-burning, hideous disasters? I mean, "Ba Oh: The Visitor" is not a new title, nor was the "Orotsukidoji" ("Legend of the Overfiend") series, or many other quite bad titles; "MD Geist", anyone? Nor is fanservice particularly new, as anyone who has seen the "Dirty Pair" movies - or for that matter, "Orotsukidoji", which invented tentacle porn - can attest.
I posit to you all that any particular 10-year "slice" of anime/manga history has, in fact, roughly the same percentage of gems amongst the dross. Now, in more recent years, that sampling can become a lot more overwhelming, as the industry continues to expand and produce more and more titles per year (also from more countries), but I still think the "gems-to-dross" ratio remains fairly constant. I mean, can anyone here REALLY argue that the "Natsume Yuujinchou" series is crap? What about "Macross Frontier"? We all know I could go on, naming many superior titles, right?
I think that Miyazaki is at least partially suffering the "This damn new generation!" syndrome that most older folks fall into. While he does identify some troubling trends in the industry, I think he doesn't acknowledge the positive ones at all.