You've misunderstood the fundamental UNIX nature of these quotes. They are said by people who use the tools in question regularly. jwz doesn't avoid regular expressions for everything (he'd be a fool to do so, and he's no fool)...he's merely pointing out that regexes can be misused, and often are. Likewise Awk.

By cloistering yourself into Lisp, and nothing but, you're missing out on years of aggregate wisdom from some of the smartest people in computing. Lisp is one of those really valuable pieces of wisdom. But it is not the only one, or even the most important. Deny yourself the rest of the history of computing, and you are doomed to reimplement it...and you'll almost certainly do it poorly.