Articles are the exception, rather than the rule, in the world's languages. Japanese doesn't use them either, nor do Finnish, Turkish, Indonesian and a host of African and Native American languages.
They are common in the Indo-European and Semitic languages, but not universal. (Hindi, Albanian and most of the Slavic languages do not use them.) Since these two families are spoken by people who have been neighbors for thousands of years, it's quite possible that one borrowed the concept from the other, an instance of the sprachbund phenomenon. But they are much less common in other language families.
In fact, the ancient Indo-European languages did not have articles, strongly suggesting that Proto-Indo-European did not. So it may be something that arose to fill a need as civilizations advanced from the Paleolithic Era through the Neolithic, the rise of civilizations, the Bronze Age and the Iron Age.
Greek was the first Western Indo-European language to develop the article (in the Iron Age), and it has only a definite article, no indefinite. This is similar to Hebrew and Arabic, members of the Semitic branch of the Afroasiatic family.
In the Germanic languages, the definite article evolved from correlative pronouns like "that." In the Romance languages, they came from the third-person pronouns, "he/she/it/they." There appears to be no "standard" evolution of definite articles. The indefinite article, on the other hand, seems to always develop from the number "one": ein, eine in German, un, una in Spanish. This is just an educated guess since I know nothing about indefinite articles in other language families.
English-language newspaper headlines routinely omit articles, and we have no trouble at all understanding them. I've often suggested that they are just "noise words" that contribute nothing to the meaning of a sentence. Yet since our ancestors went to a lot of trouble to invent them, this cannot have always been true.
I'm sure Neugierig finds his friend's article-free English easy enough to understand, merely odd.