I think the author has good points, but from where I sit they seem fairly subjective.

I've written Python for several years, and as a result the way I reason about problems have been heavily influenced by it.

I'm fluent in Ruby as well, but it takes mental effort for me to conform to its "flow", for lack of a better term. My time in Ruby has made me a better Python programmer, too - I understand more fully the idea of a DSL and how it should work. Ruby is great for writing DSLs and writing concise code that's guided by the language of the domain in which you're working.

I'm competent in Clojure, which if nothing else has given me a distinct distaste for impure functions - if a Python function takes an array, it should not modify that array in place unless it's very clear from the name that's it's going to do so, and a function should not both modify its input and return it.

At the end of the day, Python is still the language that I reach for whenever I'm writing pretty much any personal project. It's clean, easy to read, and the overall feel of the language guides me to write maintainable code.