> Not many young people know Perl or Tcl (or even lisp for that matter).

I don't know perl and I'm not young, but I do understand and appreciate the role perl -e plays as an extension of bash. When I run into an issue where I need more than bash, but less than python, I'll search around SO for a perl -e command for what I need.

This is often how people decide to learn a tool: they have a problem for which it is the best solution. They get some exposure to the capability and slowly expand on their knowledge.