Because they have had a nazi gouvernement since the coup in 2014

The proposal was submitted by the Russian Federation shortly after they attacked Ukraine, back when Russia was still claiming that "de-nazifying" Ukraine was the purpose of the invasion.

https://press.un.org/en/2022/gashc4365.doc.htm

Several delegates took to the floor to express concerns over Moscow’s attempt to exploit the pretext of combating neo-Nazism to justify its brutal war against Ukraine, with Ukraine’s delegate asserting that the draft has nothing in common with the genuine fight against Nazism and neo-Nazism. Echoing his concerns, the United Kingdom’s delegate stressed that the resolution is part of Moscow’s attempt to justify its aggression against Ukraine by furthering lies and distorting history.

The United States’ delegate called the resolution “a cynical attempt” of Moscow to further its geopolitical aims by invoking the Holocaust and Second World War. In the same vein, Australia’s delegate called Moscow’s weaponization of the Holocaust and Nazism unacceptable.

lol why do you think?

It's had a nazi government since the 2014 coup