Feature or bug?
There can be no question that commerce and political union tend to favor the Big Languages and marginalize other "little" languages such as Scottish Gaelic, Irish Gaelic, Navajo , Quechua, etc. I think mankind has a tendency towards monolingualism. Certainly nationalists, almost invariably, favor one official national language. So I do not believe a little Babel is bulit into the human soul.
Quite the contrary. One has to invest in and work at maintaining a bilingual household or to encourage polyglotism.
However, a healthy bilingualism is possible over a long term: Switzerland is a good example. Canada (English and French) is another. The United States seems to be permanently bilingual Spanish/English in some regions. Another example would be Israel (Hebrew and English). But I would say that Israel did not have to reach into the past to revive Hebrew. Hebrew has always been a language that has been studied and spoken aloud. In modern times it merely replaced Yiddish or Ladino. But we recall Yiddish and Ladino were often written with Hebrew characters.
However, Official bilingualism, as it is called in Anglophone Canada, detracts from multiculturalism because it unfairly prioritizes French over other minority languages. Scottish Gaelic is still spoken in Nova Scotia but has diminished greatly since 1900 and has had little government support. The same is true for Canada's indigenous languages.
But French like English is a Big Language or culture language not unlike Latin or Greek in their time.
St. Patrick could (probably )speak at least two Celtic dialects -Old Irish and British) but he wrote almost exclusively in Latin.
Why? Because Latin was a "Big Language" or culture language in a way Irish Gaelic was not. So historically Big Languages (languages that are commercially or culturally important) are more likely to be a Koine or lingua franca) and so therefore much more likely to survive over a long period of time.
Italian is a lesser BIg Language and so is German BUT both these languages are such powerful cultural languages (with a vast literature and musical culture) that their songs will be sung for centuries all over the world. Arabic, Chinese, Portuguese all seem to have a guaranteed future.
I have been a student of languages all of my life and now in retirement I am studying Modern Greek and Ancient Greek as well as reading Latin every day. Most of the languages I study have strong associations with literature, poetry and song. I have read most international literature in translation, of course, but when I have read poetry or songs in their original I know that translations are not sufficient so I try whenever possible to study bilingual texts and the original versions.
Each language is indeed God's work of art. Official bilingualism may not be possible everywhere but I think language studies are very important for everyone and that we should respect the cultures and languages of others.
As someone with both an M.A. and Ph.D. in linguistics (UT Austin 1964 and 1974, respectively), I found Brands' and Munro's discussions fascinating. Let me share a humorous story which was a segment on the CBS Evening News several decades ago. The story was about a scholar in Israel who was trying to increase the use of Yiddish there. However, even his own children didn't want to learn it, preferring to answer in Hebrew when dad spoke in Yiddish. The reporter asked the father "why are you so insistent on your kids learning Yiddish?" He replied: "So they won't forget they're Jewish." In other words, he considered Hebrew to be the language of the secular state of Israel, whereas for him one felt one's "Jewishness" only through the medium of Yiddish.