The article contradicts itself, and thereby exposes its Russian-centrism. Read the last sentence:
... Gorbachev's success in the West is based on the fact that he became the first Soviet leader who smiled to people in public. Many [Americans] perceived [Gorbachev] as a person who was open to communication and therefore not dangerous.
So how exactly does a smile in America "not mean anything really" when it allows Americans to distinguish people in their society who are open to communication from those who aren't? That's a very clear social function, full of meaning if you ask me.
TL;DR: in American society, smile serves two functions: (1) to express emotion of happiness/satisfaction, (2) to signify that one is "open to communication, while in Russian society the role of smile is exclusively tied to (1). Failure to perceive the dual-purpose role of smile can lead a Russian to conclude that smile has no function at all in American society (not "meaningful"). Similarly, failure to perceive the singular role of smile in Russian society, can lead an American to incorrectly conclude that all Russians are "closed to communication."
I think you're getting to the point of it: the smile vs. no smile decision is about the default "communicate with me" or "don't communicate with me" posture.
This is much like how midwestern and southern visitors perceive northeastern cities in the US. Although I've found strangers in Boston perfectly accommodating, they tend to be rather less ebullient about it than elsewhere in the US.
Well, this is all anecdotal, so these are my observations as a Soviet-born, Israeli-raised, now-American.
... Gorbachev's success in the West is based on the fact that he became the first Soviet leader who smiled to people in public. Many [Americans] perceived [Gorbachev] as a person who was open to communication and therefore not dangerous.
So how exactly does a smile in America "not mean anything really" when it allows Americans to distinguish people in their society who are open to communication from those who aren't? That's a very clear social function, full of meaning if you ask me.
TL;DR: in American society, smile serves two functions: (1) to express emotion of happiness/satisfaction, (2) to signify that one is "open to communication, while in Russian society the role of smile is exclusively tied to (1). Failure to perceive the dual-purpose role of smile can lead a Russian to conclude that smile has no function at all in American society (not "meaningful"). Similarly, failure to perceive the singular role of smile in Russian society, can lead an American to incorrectly conclude that all Russians are "closed to communication."