In the late 90s I was on a US project which included a small Dutch software company. The founder told me about Dutch people who had been living in the US for thirty plus years, speaking perfect English, now in nursing homes, who with age or dementia or whatever, can lose their ability to speak English. They revert to their native language only. I've never heard of this as an issue again, but I wondered how this might turn into a serious problem caring for many immigrant people who lose the ability to speak English in their later years.
Same thing has happened in Sweden. There's a cohort of elderly people who arrived to the country as children during WW2, e.g., from Finland. Many were under 10 when they arrived, and now that they have gotten old, some of them have lost most of their ability to speak Swedish, and are only able to speak in their native language from early childhood.
In her last days, my 101 year old friend partially reverted to German. She was born here, but German was spoken in the household when she was young. By the time she was in grade school, she was fluent in English and used English as her primary language for the remainder of her life. Practically speaking, it was her native tongue.
Her daughter didn't speak German, so I helped translate a few things -- simple comments and exclamations -- until she passed. She didn't lose her English wholly, but depending upon her state of mind, she might be speaking in one or the other language -- as I recall, she might have had trouble with English in those German moments.
From the article title I thought this article would be why FORTRAN, LISP, and COBOL still survive after over 60 years of use. First, these computer languages started with a lot of good ideas and evolved to incorporate ideas from subsequent decades like structured programming and objects. Second, there are massive institutional code bases in these early languages that are too difficult to rewrite.
These languages might even make it into the 22nd century.
