The Soviet Union did not have the capacity to withstand the expected losses in the European Theater for very long.
Soviet planning of the era revolved around maintaining operational and strategic initiative at all costs, and fighting an offensive war. The hinge point was how quickly the red army could break through and gain operational freedom versus how quickly the U.S could land a resupply and reinforcement effort in Europe. Soviet planners give very narrow chances for success.
This hasn't got much to do with Soviet preparedness in the 80's, and the soviets had fully mechanized their division and motorized their logistics tail by then.
Lend-lease did contribute significantly to the soviet's logistic capacity in the second world war, notably the jeep and the deuce-and-a-half Studebaker trucks, both regarded very highly and subsequently used as model designs for the UAZ And Zil.
Soviet planning of the era revolved around maintaining operational and strategic initiative at all costs, and fighting an offensive war. The hinge point was how quickly the red army could break through and gain operational freedom versus how quickly the U.S could land a resupply and reinforcement effort in Europe. Soviet planners give very narrow chances for success.