That seems to reflect my lived experience. Do bilingual people in general seem to be more intelligent? I don't think so. But, like many other things in life, the access of even a second language in my opinion gives you another tool to use as intellectual leverage to gain greater or richer understanding to many specific domains that you would otherwise require someone else to digest the information for you. That doesn…
I have to imagine there are parallel benefits as well. Just as a Java developer will become a better Java developer by learning programming languages with other paradigms, I have to believe knowing multiple spoken languages has tangible benefits outside of understanding the language itself.
IMO, your programming language comparison is somewhat similar in that even knowing multiple, similar languages allows you to differentiate between the syntax and the concepts expressed by the syntax. E.g. different ways of constructing classes and objects in different languages will make you understand the core of OOP better, similarly to different ways to loop, etc.