A Scot and an Englishman can both be called British because they come from an Island called Great Britain, it has nothing to do with ethnicity. By contrast Ukranians and western Russians can both be called European.agreed, but a scot and an englishman can be called British, no such thing with UKR and RUS
The point is, the main ethnic group of Russia is ethnic Slavs, the main ethnic group of Ukraine is ethnic Slavs. "Ethnic Russians" are not a thing, it's just a propaganda phrase Putin is using to try and make his **** stick because he knows it applies to damn near 100% of people in Ukraine as the two nations share a core ethnic group.