To me, it seems PHP is the Windows of web languages. In many respects it "sucks", can be clunky, and has little to no elegance from a formal perspective, but it's everywhere and everyone knows how to use it. Thence lies its success.

(however, if you're willing to give up lambda's, some of the PHP frameworks like Cake are only mildly unpleasant)

P.S. Also, the author is inaccurate, as many of those functions are only included in certain modules and rarely found in common PHP builds.