Because it's an interesting fact. Lots of articles talk about SV startups, Berlin startups, London startups etc. I find it interesting to know where the company

Because it's an interesting fact. Lots of articles talk about SV startups, Berlin startups, London startups etc. I find it interesting to know where the company is from. If the BBC was reporting on a 'British startup' you could consider that nationalistic (although I wouldn't). But a British news company mentioning the country of a foreign startup is hardly nationalistic in any way.