If you're not already good at something, of course it's easy to say something else doesn't work or isn't any good.
For a good summary, watch Steve Yegge's presentation, "How to Ignore Marketing and Become Irrelevant in Two Easy Steps". (http://blip.tv/file/319044/)
Marketing is often what developers brush off as "the other stuff" without really understanding it.
Agreed. Trying to convince programmers to not write it off entirely (such as in the presentation) is a step in the right direction.
FWIW, I think a few languages (Python, for one) have actually been marketed reasonably well.
This has improved with mongrel_cluster and (more recently) Passenger, but the memory footprint for a Rails application continues to be an issue, even relative to other dynamic languages.
Interpreter level threads and multi-process based techniques have tended to be common approaches in both various Perl and Ruby projects I've worked with.