Someone in Vietnam released software to the world, therefore this is a story about American culture. That's just how Americans think. It's also necessarily about modern American culture, even if you know absolutely nothing about the past.
Not a "just how Americans think" issue, a "what is relevant to our readers' lives" issue.
That's absolutely not the case in other places of the world. In some cases, even the opposite problem arises (that is, discriminating against your own country/culture and favouring a foreign one)
(To note, the article wasn't about American culture, it was a personal interest piece on a person who was unprepared for the effects of the success he experienced.)
If by "other places in the world" you mean areas that are small enough or have an ephemeral-enough regional identity to have developed strong codependent identities with other regions, then I would certainly agree.
Living in a number of places has shown me that, in larger countries/communities with defined identities, internally facing publications will publish stories that are strongly relevant to their reader.
Because, as I said, it wouldn't make a lot of sense to spend that sort of space on an article that wasn't relevant to the reader.
Cultural diversity (and exceptionalism, etc) is all rolled into the DNA of the country.