“Russians by definition cannot be Nazis.”
Nope, Russians can be Nazis. Hell, Jews can be Nazis as we see with these disgusting Nazi-suckup Jews in Ukraine. There are absolutely Nazi groups in Russia. They are radical Russian ethnic nationalists who want to throw everyone who is not a Russian out of the country. This charming dissident Alexei Navalny with his fake poisonings is one of these types. However, they are not common, Putin hates them (Putin is Jewish), and their organizations are banned.
Much more common are “Russian Empire” nationalists. They are not ethnic nationalists. The worst they get is, “You have to speak Russian as a native tongue and be Russian Orthodox in religion.” If you ask them if you have to be Russian to join, they will say, “No! We are not Nazis.” Russians have always been multiethnic and multireligious. Many of the greatest heroes of Russia were non-Russians. Many of the ethnic groups still speak their native languages. Every Chechen I saw so far was speaking Chechen.
Russia nationalism is the nationalism of a multiethnic multireligious empire. Even the rightwingers are typically not racist.