Should we call them Soviet scientists then? Neither Russian science nor (esp.) Ukrainian science can be taken individually.

Bogolyubov and Korolyev both are Russian names. Bogolyubov was born in Russia and he didn't speak any Ukranian, which maybe important here.

I don't have a skin in the game. If Bogolyubov then came to US and did some research here, we could call him Russian born Ukranian-American.

It's OK to list all the affiliations, it is not OK to pick and choose.

"Russian" is correct (technicality, as this was indeed his nationality specified in the passport) but incomplete. Just "Ukranian" is incorrect.

Yeah, we can do better. This conversation is an example how things could be blown out of proportion.

Indeed the original draft said USSR, but we are talking about Russian theories, not USSR scientists who are ethnically Ukrainian. We came to realize that we have so little information about the exact theory and our best knowledge suggests that the theory is, while may or may not have been pioneered by a Ukrainian scientist (see the updated post), currently rooted in Russia and not in the former USSR.

> Nikolay Bogolyubov was born on 21 August 1909 in Nizhny Novgorod, Russian Empire to Russian Orthodox Church priest and seminary teacher of theology, psychology and philosophy Nikolay Mikhaylovich Bogolyubov, and Olga Nikolayevna Bogolyubova, a teacher of music

By your logic Euler is Russian

It's not a "tendency", it's truth. All people you mention are Russians because they were living in USSR, speaking Russian language, worked in Russia and for them Ukraine was an administrative region. Not to mention the fact that the country that denies Soviet legacy and achievement does not have moral right to attribute anything that has been done during the period to people and regime which despises their own past, legacy, sacrifices, relatives, and denies everything that has been done. So ridiculous.