You can't entirely dismiss longing for past dreams as pure nostalgia. There are good reasons why some parts of the aesthetics of Lisp, older OSes and programming practices from the past are appealing. In particular, Lisp is a mania pill that makes you believe you can build anything you want (see
http://marktarver.com/bipolar.html). The other main attractive point is the (at least perceived) lack of bloat compared to modern systems. We now need what is practically a supercomputer just to browse webpages and check dubs.
Mobile OSes shit on both of those ideas: massive and visible bloat is A-ok and tablets are crappy as development platforms. The final nail in the coffin is of course web standards and current web dev practices. In wake of this, declinism does not seem so irrational, does it?