The Soviets definitely have the resources to keep going for a solid year. That is enough time for them to smash the WAllies back across the Rhine (at minimum) or even off the continent (at maximum). But after that year, things start getting difficult.
The Western powers command air forces that can operate continuously the Soviet VVS by contrast was reliant on surges of effort.
From 1943-1945, the VVS operated continuously against the Germans. Western Allied air power is only worthwhile if there is a long-war. Airpower needs breathing space to be really effective. Allied air-power in Normandy in 1944 pinned the Germans down, but it did so at the end of a long campaign spanning years to pound German industry, cripple their transportation networks, and destroy their air force. When the rebuilt Red Air Force clashed with the Luftwaffe over Kursk, the air battles were titanic, but the two air forces largely canceled each other out. As a result, neither side's air power played much of a part in the decisive ground battles. In this scenario, both sides would start with vast, experienced, and effective air forces. There would have been no long campaign before the initial land war in which the air forces could slowly soften up the defences, and whittle away the threat - it would have been an immediate dive into a colossal air battle. By the time the WAllies had managed to win this, the initial ground battles might well be over. During this period of air parity, the advantage goes to the one with more powerful ground forces... which is the Red Army.
Not to mention but war is not decided by tanks but artillery, the Red had great numbers of tanks in 1941 but the German artillery killed them in numbers. American artillery fire control systems are far superior to the Germans and the Germans had superior artillery doctrine to the Soviets and the British artillery doctrine is even better.
This is the Soviet Union in 1945, not 1941. The Soviets had massive artillery stocks that far outstripped what the Americans and British had in quantity and just as good doctrine. The Anglo-Americans neither experienced nor employed artillery on the scale of the late-war Red Army, where multiple Breakthrough and Rocket Artillery Divisions would be massed and annihilate German defenses wholesale.
Further but the British and Americans and their allies are far better equipped with anti-tank weapons than the Germans
Which would be flushed out by infantry and artillery, as the Germans were.
also their entire forces are motorised or mechanised.
And yet they never managed successful offensive operations on the scale of such operations as Barbarossa or Bagration. They also never faced an offensive on the scale of a Soviet late-war operation or any German operations against the Soviet Union in 1941-1943.
Finally British and American tanks are quite effective at close range, the Red Army's tank drivers had only one tactic, drive in close
You... really know nothing about how Soviet tank formations operated, do you?
Anglo-American strategic bomber forces will not be targeted against the USSR's industries at least at first but rather against the supply and on occasion front lines.
Where they will largely hit dummy and decoy targets, while the painstakingly camouflaged real targets continue to happily function on. The WAllies will eventually cotton on to this, but given their over-reliance on signals and air intelligence, it will take awhile.
For the record... a neat little comparison of Soviet late-war major operations versus Anglo-American late-war major operations:
The [Western] Allied strategic formula began with a massive air attack by heavy bombers, heavy artillery concentrations, tactical airstrikes, and an attempt to penetrate the German defense with first-echelon assault divisions. Frontages were narrow; in some cases, though theoretically of division level, the thrusts were on narrow brigade, or often battalion, and even company, frontages (i.e. Goodwood, Atlantic, Spring, Totalize). Penetration was followed by a prolonged break-in battle that generally exhausted the enemy but did not annihilate him. In contrast, the Soviet strategic offensive destroyed enemy defenses completely and quickly tore the front apart to expose, engage, and overwhelm enemy operational reserves. Once a breakthrough was achieved, and the Soviet tank armies acquired operational maneuver, there was little the Germans could do except give ground and wait for exhaustion and logistic difficulties to stop the Russians.
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The Soviet approach was direct. First, eliminate the dogfight for successive defense lines; second, and most important, cut out the shoulders of the breakthrough; and, finally, restore the deep battle: kill off headquarters and operational reserves before they arrive at the front. The method was elemental-destroy everything. Do not attack hoping for the spearhead to breakthrough and then pour troops through the breach as in France in 1940; instead, rip out a chunk that is 35-75 (60-120 kilometers) wide. The enemy cannot hold the shoulders if your initial attack destroys his entire upper torso, with "large scale enemy losses, the enemy is not able to close the gaps and forced to execute the maneuver of deep reserves and take forces from strategic directions." The Soviet strategic offensive solved the problemn with chess-like precision, simply, elegantly, and savagely: tear away a 60 miles of front, insert a massive second echelon, and tear away another 125 miles of rear areas and operational reserves. Simultaneously, send out OMGs (Operational Maneuver Groups, ie: Tank Armies) to keep the operational and strategic counterplans irrelevant.
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Bradly and Montgomery's operational art was to claw away until something gave. Clearly, the spot for the strategic offensive was the Caen area and not the US Army's bocage-cursed front. Deep operations appeared after Avranches, but were initiated by divisional commanders and immediately made Montgomery, and especially Bradley, apprehensive. Patton radiated a sense for the operational system but lacked the horses to carry it out. When he did try, it was under the conservative rein of his boss. Senior Western Generals were not as good as their Soviet counterparts. It will be suggested that the Soviets had had four years to practice. It should be noted the Western Allies (especially the British) had five.
To summarize the above: Western Allied ground offensives largely broke into enemy defenses, fought their way through them, and (if they didn't exhaust themselves doing that last step) then broke out. This conserved lives, but wasted time and produced less results in terms of casualties inflicted upon the enemy and territory gained. The exceptions was where the enemy had already been whittled away so much that they were bound to collapse under Allied pressure anyways (as happened with Cobra and the Allied offensives over the Rhine). There were no attempts to coordinate separate ground offensives. Soviet offensives, in contrast, obliterated enemy defenses in the opening blow and then powered their way forward with overwhelming force until the offensive was exhausted. This was more expensive in terms of lives, but was much faster and inflicted devastating losses in men, equipment, and territory upon the enemy. Furthermore, Soviet ground offensives were coordinated to be executed either simultaneously or in sequence so as to support one another.
The Soviet economy will struggle to maintain war production without Western inputs.
In 1945, Western inputs dried up. The Soviet economy kept going.