Do you really believe that? Russia has taken huge toll to get 30% of Ukraine, manpower, wrecked economy, and rouble.. your thesis is they will magically get Ukraine and suddenly have enough power to takeover Europe?
Discussion
It's possible. When they get Ukraine they get Ukraine's resources in addition to their own. More fuel for the fire. Not saying an ongoing series of conquests is a sustainable business model but hey it kept the Roman empire in business for a couple of centuries.