I speak conversational Russian, Latvian, German and Portuguese. Add fluent or nearly fluent Italian, Spanish, Catalan and French, all of which I've spoken in my sleep. So I'm far more qualified than you are to determine what's a dialect and what's a language. Definition of a dialect: a language without an army and a navy--Max Weinreich.

You need to read this: https://medium.com/lessons-from-history/lost-in-russified-whataboutistan-3b6d27874592

National identity is a bottom up, not a top-down matter. Americans were Brits....until they weren't.

Czechs, Slovaks, Slovenes, Bosnians, Croats, Macedonians and Albanians were Austro-Hungarians until 1918....when they weren't.

Slovaks were Czechoslovaks....until they weren't.

Scots are Brits, and Catalans are Spaniards.....until they might not be.

And take Tim Snyder's Yale course The Making of Modern Ukraine (free on youtube!). https://www.youtube.com/watch?v=nLfFmYWjHtc

Denying the existence of Ukraine and Ukrainians is genocidal and puts you in the same class as this crowd: https://www.justsecurity.org/81789/russias-eliminationist-rhetoric-against-ukraine-a-collection/