I sometimes wish my childhood environment were conducive to holding onto a second language. I took Spanish in high school but because there was nobody around to speak it with I lost it entirely.
I’m now working on acquiring a second language I might actually get some usage out of, but nothing can parallel learning secondary languages early on.
From an evolutionary perspective it makes no sense either. Multilingualism would happen sometimes, but it was only when your tribe was conquered by a neighbor. Other multi lingual scenarios are very recent. If there are any evolutionarily rooted features around this, it would be related to the former. Though, there could still be some coincidental benefit, it just seems as unlikely as any other totally coincidental benefit.
I’m now working on acquiring a second language I might actually get some usage out of, but nothing can parallel learning secondary languages early on.