I assume by "white Russian" you really mean someone of Russian ethnicity and not Belarus - which is what that phrase means to a Russian speaker - but you might want to clarify.
A friend of mine had a grandfather, who was born in central Asia (Samarkand) had Ukrainian parents, but also had written in his passport that he was a russian. Soviets erased his roots, history, ethnicity. He never spoke Ukrainian in his life.
Btw, that is what current russian government is doing. They have stolen thousands of Ukrainian kids and erased their identity. Few more years and some of them are ready to be sent to the frontline.
At least Belorussians and Ukrainians can speak Russian without an accent despite knowing their own languages.
> Soviets erased his ...
I doubt the USSR had such power solely on its own. It depends mostly on the will of parents (and grandparents) and the type of a young person. If a kid likes art, it's more likely the kid would be interested in national memory, if a kid is more into tech, then it seems not that important, which nevertheless can change later.
Russian Germans (not necessary all of them) consider themselves as Germans even after hundreds of years living in Russian Empire and then in the USSR.
They didn't succeed in completely crushing all national memories, but a few more decades and who knows what might have happened.
The culture has been preserved using non-provocative way by not mixing it with politic. Surely we must be respectful and thankful to those going rather provocative way and suffering.
The daily Soviet system issues have been successfully mentioned in a subtle way in films since middle 60s, which became classic. I'm not aware of similar from movies from China.
Famous Belorussian and Ukrainian songs have been performed in public on radio, TV in the USSR.
Even today some western world artists say, that sure, of course, the culture is not separate from politic while the others say they are doing art not politics and welcome questions about their public art not their private political opinions and preferences. Similar to many singers and actors dislike questions about their private life and lovers instead of what actually matters: their art of doing music, singing, performing.
> ... what might have happened.
Since middle 80s the level of freedom started rapidly to increase.
Local cultural symbols themselves were seen as "political" and "provocative". The definition of political and provocative was broad.
Small bits a pieces passing through the barriers are not "it".
But the policy in the early Soviet Union was in fact opposite:
That is a pure victim blaming. If the system makes it dangerous to teach your kids your culture, most parents will no do it.
Nowadays for singing Ukrainian songs you can go to the russian prison. Imagine what could be under the Stalin rule.
> singing Ukrainian songs you can go to the russian prison
I'm not sure how is this right now, I fear it got worse, but on August 2022 it was possible(*). Russian guitarist performed a Ukrainian song in Ukrainian original in public:
https://www.youtube.com/watch?v=tPu5WQKXsjM (cut)
https://www.youtube.com/watch?v=82argH8zZXQ&t=1041s (full, 10.89 million views)
And it is not just some beautiful Ukrainian song. It is a prominent "I will not surrender without a fight" (2005). Which sounds provocative enough these days. Yeah, he did not continue doing it again and again, thus it's by no means a prove one can safely practice this on a daily basis.
This song must be known by almost every Russian (and Belorussian), since this song was used once Zelensky played the main male role in the rus-ukr movie "Office Romance. Our Time" (2011) remake of the famous 1977 USSR original.
OTOH one of the most prominent (former) Ukrainian singers and since 2014 Russian singer Taisia Povaliy could sing her Ukrainian songs on December 2024 at the main State Kremlin Palace in Moscow. (Obviously, because she openly supports the state.)
[1] https://www.mk.ru/social/2024/12/11/marshal-kadysheva-buynov... (rus.)