I can't get to the original article, but I assume that this is documented there. Yes, I think it's silly to require proficiency in a certain language. Google does not have this requirement. You must know a programming language well enough to be an expert, but it doesn't have to be Java/C++/Python/Go.

Also, FWIW, Google intern interviews and full-time interviews are completely different. Interns must interview like everyone else after their internship to be converted to full-time employees.