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I don't really believe this. Of course some people have more of a tendency to be good at languages than others but I think the guy from you story probably didn't try hard enough or maybe had a completely wrong approach. There are many countries where virtually all people speak a foreign language which shows that it is possible for almost anybody to pick up another language.
There is a theory that children have a "language acquisition device" that goes from muscular brawn to a flubby dough-boy with age in most people. IDK if that's accurate but there does seem to be something to it. The countries where everybody is multi-lingual this almost assuredly happens in middle to early childhood.
The fact is any adult can learn any language, they just either don’t have to or don’t want to. I’m not saying it’s easy or it’s the best decision for every situation, but it’s definitely possible. This is true even more so if it’s a popular language with a lot of resources to learn it, and you live in the country where practice is virtually free.