I live in Poland. I was in Ukraine many times. I work with Russian- and Ukrainian-speaking Ukrainians. My cousin married an Ukrainian. There's millions of them here. Literally nobody except for Russian propagandists ever complained about abuse of Russian-speaking Ukrainians.
Kyiv (the capital) was mostly Russian-speaking till very recently. Most of Ukrainian politicians up to this point were Russian speaking. All 3 western-leaning presidents of Ukraine - Poroshenko, Yushchenko, Zelenski - come from eastern Ukraine and were speaking Russian as their first language.
Most Ukrainians speak both languages and switch depending on the context.
It changed not because of some imagined persecution, but because Ukrainians started to associate Russian language with invaders and genociders.
As for neo-nazis exerting control - neonazis tried to run for parliament after 2014. They got 0.7% of votes.
There's more neonazis in one russian division than that.
None of what has happened in Ukraine in the past 20 years justifies the invasion.
None of it justifies the Russians rape and torture of civilians.
None of it justifies the litany of war crimes including castrating PoWs and committing genocide.
So why are you trying so hard to justify it?.