I feel the same about Latin's elegance which I learned in the 70s in high school. More recently I have mastered Russian and find the same kind of elegance and ability to convey a lot in a few words. There are all kinds of two word and four word sentences used by Russian people as a kind of poetic shorthand about life's situations. And Russians, young and old, men and women, professional and blue-collar, have a love of great poetry and lyrics. They will often write their own and share with others as a toast, or just an impromptu performance at a party.

I recommend learning Russian, which is much easier than English to learn, partly because its grammar is a lot simpler than Latin (or Romance languages) while at the same time having a much more regular vocabulary than English.

I think one reason why the authors chose language learning as an example is that mastering a language, even part way, is a long term commitment over many years, and that it is the frequent and long term effort that has the effect on the brain.