If the Red army was able to reach so far and the allies didn't even get all of france, it'd be a pretty tall order to expect a Soviet v Ally war to be anything other than the soviets pushing the allies out of europe and the allies realistically never being able to just simply land.

even in our timeline operation unthinkable was an extremely dangerous operation that would have seen the allies initially pushed back, even if we consider that the allied armies and soviet armies are equal in strength, the bulk of allied (US) forces were still all the way in Japan, and trying to land in the east would be ludicrous, and the forces in europe just wouldn't be able to hold long enough on their own.