I don't believe that Emacs is dead at all. Actually, most of the problems (multithreading, libraries, file I/O) raised by this article can be solved by replacing Emacs Lisp backend with Guile, which is an active and promising project [1,2]. As for Emacs philosophy, it might even survive Emacs (in the hypothetical situation where Emacs dies) if a project such as Emacsy (the second one presented in [1]) takes off.
[1] https://lists.gnu.org/archive/html/guile-user/2013-05/msg000...
[2] https://www.google-melange.com/gsoc/proposal/review/google/g...