TBF I think he has that backwards - the Ukrainian identity is the direct result of being ruled by Russia. Without it there really wouldn’t be a Ukraine.
300-400 years ago there was not a distinctive Ukrainian polity; they really were several groups of Slavic types mixed in with all the Slavic groups that made up Muscovy. It was the chauvinism of those who defined themselves as Russian (and therefore fit to rule) and everyone else as “others” that created a genuinely Ukrainian feeling.
It was the traumas of the 19th and 20th centuries that reinforced it that feeling into an identity and its this war - whether they win or lose it - that will cement it as a country.
I’d suggest that is a somewhat limited understanding of Ukrainian history. The roots of Ukrainian identity trace back to the Kyivan Rus’, a powerful medieval state that existed from the 9th to the 13th centuries, long before Muscovy emerged. Kyivan Rus’ was a cultural and political entity that laid the foundations for what we now know as Ukrainian, Belarusian, and Russian identities. It wasn’t Russias doing.
Ukrainian language and cultural practices have distinct characteristics that evolved over centuries. By the time Muscovy started to consolidate its power, Ukrainian culture and identity had already diverged significantly from those in the north.
Western Ukraine, particularly Galicia, was under Austro-Hungarian rule, not Russian. This region experienced a different set of influences and developed its own sense of Ukrainian identity distinct from that under Russian control. Similarly, the Crimean Tatars.
The traumas of the 19th and 20th centuries, such as the Holodomor, Soviet repressions, and World War II, were indeed significant. However, these events did not create Ukrainian identity; rather, they reinforced and highlighted the resilience of an already existing national consciousness. Russian settlements have attempted to cleanse Ukrainians and Ukrainian culture from the areas that it occupies, much as the Israeli’s are doing in Palestine.
Ukrainian identity is rooted in a complex historical process that predates Russian rule and is influenced by a variety of cultural, political, and social factors. While Russian dominance has impacted Ukrainian identity, it is not the sole nor primary source of its existence. Ukrainian national consciousness has been shaped by a myriad of influences and events, demonstrating a robust and independent culture and community.