You should consider cities or regions as namespaces and not countries like tld, because as you see with Ukraine, Kosovo etc they change. Birthcity or village remains through generations. Language is also very crowded, names just arent unique.
I don't want my identity tied to my city or region. I might not want to give out my birth city, or I may simply not identify with it anymore.
Forced namespacing is just a poor solution. Users can add whatever namespaces they want to their own username if they want to, after all, it's just a string.