Its valid criticism in the same way that you criticize moe and ecchi shows for being designed exactly that what they are designed to be.
In the end it all comes down to taste, preference and opinions.
Fair enough, but I think there's something of a difference in that episodic storytelling is a model that's as old as storytelling itself, and even if it's personally not your taste, it's a simple affair to come up with examples that have something worthwhile or compelling to say. Whereas shows about cute girls sitting around eating cake, or a story about a milquetoast guy who has ten hot chicks falling over him for no discernible reason...kinda more difficult to think of examples. (School Days, maybe? :trollface:)
Miyazaki is an old geezer who has retired like 5 times already. I take his ramblings with a grain of salt 
But yeah there is an ungoing trend of the anime industry overspecializing themselves toward the otaku market. And they can keep doing that because japanese otaku's keep on being willing to buy #13 in a dozen harem anime obscenely overprized BD's and DVD's. This is actually pretty well known by most anime watchers by now I think.
You're exactly right, but therein lies the problem: the more you try to target that insular audience with almost focus-group-created shows you know they'll snap up, the more you limit your ability to tell a breadth of good stories. They'll still get made, but they'll just be fewer in number and harder to pick out. I don't think we'll ever see a repeat the sheer creative explosion of the huge OVA boom of the early 90s, or the glut of high-quality stuff from the later 90s to early 00s; the market's just too different. It's also not much of a sound long-term strategy either: Japan's burgeoning demographics crisis is no secret, so the age group the industry is going for will just continue to shrink over time. At some point that well's going to start to dry up, and then what?
It's not even a problem limited to anime, either: I know at least one really prominent Japanese games developer (can't remember who) has repeatedly spoken out about the state of his domestic industry, and how Japan's output is increasingly niche (outside of big universal tentpole stuff like Nintendo IPs) and less relevant. Back in the 80s and 90s, Japan
owned gaming, but unfortunately they're a far cry from it now, and I think we're all poorer for not seeing that continued variety.
But you know what? I don't even care, because I have thrown away my elitist mantle a long time ago and can enjoy even the dumbest of shows. That includes shows that involves having the main character power up his mech with ero particles by molesting women. What can I say? ¯\_(ツ)_/¯
Well, some of us haven't thrown in the towel on good taste just yet.

I mean I like some dumb stuff too, but only as popcorn entertainment; I need meaty stuff that I can chew on. I'm not a film buff at all, and I barely read anymore, but animation (so for all intents and purposes anime) is the one entertainment medium where I try and view things with more of a critical eye. I've seen the amazing stories that anime can tell, and the wonderful visuals it can use to tell them, and when you've seen the best of what the medium is capable of it's hard to be satisfied watching something sub-par.
It'd be pretty heavy as a starter series, but man, anyone who has even a passing interest in high-concept sci-fi absolutely owes it to themselves to give it a watch. There really hasn't been anything else like it, and I don't think there ever will be.
http://www.animenewsnetwork.com/news/2014-02-12/legend-of-the-galactic-heroes-novels-get-anime
There will be something like it 
Dammit, I'd almost managed to put that out of my mind.

Suffice it to say that whatever form this takes, I think it's going to be unnecessary at the very least. I mean, the original OVA project was a very talented director and his team working for
over a decade to bring the entire series of novels to life...what could a new adaptation possibly add to that. And I can almost guarantee that they're going to replace all of those beautiful cel-animated space battles with *gag* CGI.
Yes, no, and I hope not, because it apparently sucks.
I'm so totally not a fan of writing shows off based on other people's opinions without having seen anything of it myself to form a proper opinion of it.
(ya know, the thing that you are doing right there)
You might have a point if I was just reading random people on the Internets going "hurrdurr that show sux." But the opinions I'm talking about are from friends with whom I've been discussing anime for...oh man, it's been almost a decade now. I'm freakin' old. But anyway, I know their tastes well, and they know mine, and I trust them enough to put a good deal of stock in their opinions on what they've seen. Plus with this particular show, I've read enough to know the general premise and how it's pulled off, and it just doesn't seem like something I'd be on board with. Really pretty opening sequence, though.