I don't know if I believe that Guido Van Rossum has to spend 50% of his time on not making python better, but perhaps it's true. Isn't he at dropbox now as well?
Also, is Python necessarily his unicorn now? It's certainly not the same as a project that he conceives and creates - it was a long time ago, but success changes that.
"He was employed by Google from 2005 until December 7th 2012, where he spent half his time developing the Python language."
One of the reasons why Clojure is great is because Rich Hickey actually goes out there into the enterprise and has put a lot of thought into making it an extremely practical language in a wide variety of business settings, without compromising on the things that actually matter.