I'm sorry to say this article doesn't give a satisfactory answer to the question of what it takes to become a translator of literature.
In the first place, being bilingual is only the beginning. Just as many people who speak only one language aren't capable of writing a good book in that language, many people who speak a second language don't have the writing skills to translate a book into something worth reading in a second language. So translators need not only fluency in two languages but also great skill with words and passion for the language into which they translate.
Secondly, GEDs and post-graduate degrees aside, many translators acquire some sort of certificate that attests to their translation skills. To acquire such a certificate, translators must usually take an exam. This may or may not be related to any traditional degree-granting university.
Finally, a thorough understanding of the cultures of both languages is absolutely essential to the translator. In fact, many successful working translators spent years abroad to acquire that understanding, and continually keep themselves up-to-date by following the news and culture developments of the countries related to their language pairs.