I think, in many peoples minds, extensibility == pain; either lots of code configuration (hello java, ejb), or xml (hello hadoop, java, spring, ejb), or tons of code (hello java, c++), etc. When nice languages don't make things painful, it sometimes feels like it's wrong, or not really enough work, or in some other way, insufficient. But people can mistake the rituals of programming for getting actual work accomplished.

:shrug: just .02