I still read mangas. However I can at least point out that before I gained access to the internet and before it became so easy to read the small handful of mangas I do read now, I supported the industry. During Junior Highschool and all through highschool and in part after I started working a real job. I gave what I could to the industry, I bought videos, merchandise, video games (usually anime related ones). I got my friends into them and so on. However time and interest do take their toll on people. A lot of the anime that is popular now just doesn't click with him like order stuff did, or the magic of just seeing a new anime isn't there like it used to be when I was young. I can't say that he newer stuff is bad, or boring.. a lot of it just doesn't interest me as a whole. I can even remember the last time, I saw a anime that wasn't a manga I've been reading for awhile and actually watched it.
Back in my teens before anime became so prominent in the west, just seeing that non-cable stations would air dubbed anime blew my mind. It was like this thing, that you knew was going to be great and blow up into something fantastic, and it sort of did but with all that attention and more and more anime becoming localized, it was bound to happen that like any trend or fade, its crazy would fade. Kids would eventually discover new things that interest them, older fans would cling to older franchises or simply not want to embarrass themselves by continuing to support a genre of animation that at times can be some what childish, or seem perverse.
I think i said it already but i dont watch anime anymore. Not a lot of it seems aimed at older audiences and the ones that air aren't exactly my niche. Is the Industry dying? I doubt it, it might be going through a low its only because it was always a small niche here in the US to begin with. This is a niche market, parents are handing their kids mangas of One Piece or Naruto, and these shows aren't always presented on easily accessible stations. Kids in general drive in kind of market that is aimed at them, and anime for the most part is aimed at kids and teens.