IMHO this is a very localized view. We live in a global economy and worldwide there are huge numbers moving into economic classes that now have disposable income that didn't in the past. Cultural, political, and even climactic changes will have as much to do with diving's popularity as a perceived generational economic challenge in a given locale. (In other words, it's not all about me and where I live. ) All IMHO, YMMV.
Good point. If even just a tiny tiny fraction of Chinese get into the liveaboard scene, that could make up for the downward trend in Western clientele.