I think this view is delusional. NATO countries are supplying Ukraine with weapons, it's pretty conventional to consider this as being a party to the war.
The only reason we don't say it openly is that elites want to maintain pretense that we are not in a war (that's unpopular in Europe and US) and that NATO is defense-only organization.
USSR was fighting USA by supplying weapons to Korea and Vietnam?
Just a Russia Today style of whataboutism. Why you take any russian word as true? They can only lie. Whatever they say about Ukraine is a lie.
If you want to believe russians, why not believe that this Ukrainian 3-days special operation is going according 5 years plan of grinding Ukrainian soil treeline a day and pushing neutral neighboring countries to actually join NATO?
In some sense that remains true, but the war remains a stalemate after three years nonetheless. It's become clear that Russia's per-capita war fighting ability is basically garbage. They aren't a superpower, they're something more like Iran, a regional power that is big enough to be expensive to mess with but not a feasible threat to anyone but weaker neighbors.
Ukraine's infrastructure damage can be backstopped by robust trade with wealthy partners and supporters, while Russia is losing refining capacity and running out of gas. To the extent that the war represents an existential threat to either side, it's Putin that has to be more worried. Ukraine can keep this going for a decade or more, it seems like.
NATO isn't fighting in Ukraine, Ukraine is fighting in Ukraine and Russia is the stronger party in that conflict.