I don't think Stallman despised Tcl because of its EIAS (Everything is a String) philosophy. He was wary of the Tcl relationship (at that time) with Sun Microsystems, and Stallman was a longtime Lisper anyway; I wouldn't be surprised if his opinion was that everything outside of Lisp sucked.

EIAS is a powerful concept, though, which with Tcl's conceptually simple rules allow it to be homoiconic (http://en.wikipedia.org/wiki/Homoiconic) and allow for some interesting and _pleasant_ programming.

To head off one common misconception of EIAS, Tcl does not actually internally represent its code only as strings. It byte-compiles. Pure string-only parsing was replaced with byte-compiled code in 1997.