The only reason I'd assume the Go version was concurrent and the Python one wasn't is that concurrent processing in Python can be very prickly. That is by design. Guido has talked about how adding too much support for concurrency at the language level would complicate things and probably end up with a language that was very non-Pythonic.
It stalls in Python because the author is not acquainted with non-blocking system programming (the select()-call, which has been around since at least the eighties and has been a part of core Python since a very long time).
As to why a software developer who did not invest some minimal time into learning basic system programming feels qualified to write a blog post about this topic is another question.
Citation needed.
How about "he is acquainted but can't be bothered to use it retrofitted to a language not tailor made for it"?
>As to why a software developer who did not invest some minimal time into learning basic system programming feels qualified to write a blog post about this topic is another question.
And why you think you're any better than him based on a short blog post (and especially one in which he does not delve into why the Python version was slower or says it would be impossible to make it faster, just mentions it's speed in passing), is beyond me.
Maybe cut down the snark?