&gt; And why hasn’t the C world turned into a similar Tower of Babel?<p>Because it&#x27;s much harder to produce a variant of C than it is to produce a variant of Lisp.  Producing a variant of Lisp in Lisp (a.k.a. writing a macro) is a trivial exercise that anyone can do in a matter of minutes.  Producing a variant of Lisp from scratch is an elementary exercise that an undergrad can do in a couple of hours.  Producing a variant of C is an advanced exercise that would take even the most skilled programmer many days.