The problem is people who might speak Russian, but still consider themselves Ukrainian.
I went to Ireland back in 2009. Everyone I spoke to spoke English. I asked them why they didn’t speak Irish. They said they didn’t know how, or very well, learned it in school but no one in adult life talks to them in it, or they don’t want to.
They were actually, biologically Irish Celts, but chose to speak English.
You do know that speaking Russian is forbidden in Ukraine, right? You can go to jail for it.