pure speculation, because i don't know the interior history of python:

1. perl has always prided itself that "there's more than one way to do it" including repeated, prominent use of an acronym for that. see timtowtdi.

2. there is a theoretical idea kicking around out there that, if a language allowed for only one way to express any idea, then that language would be a better language (all else being equal) because if you and I always write the same code for the same task, we could easily maintain each other's work. see for example "egoless programming" or the ideas that led to Simonyi's "metaprogramming" (whether or not you agree)

3. perl is a mess

therefore, it might, given the history, make sense to say that about python as a way of trying to point out a salient difference from perl