Ukraine didn’t have concentration camps, as far as I know. It was too far east. People got killed with guns. Jewish relatives on my mother’s side were killed (as Jews) in Uman and Kiev by the German army and local Ukrainian policemen.
I have nothing against Ukrainian people whatsoever. There are good and bad people among all people. My point is simply that the author of the article is correct. There are some very unpleasant characters mixed in the nationalist movement. They are much more openly fascistic and intolerant than people currently in the Russian government even if they are unsavory for other reasons. I am sure they have plenty of Russian fascists, as well. But they are not in the government. That’s the difference.