This source claims that Germany would have defeated Russia if Hitler had listened to his generals and captured Moscow and central command, instead of redirecting Army Group Center to Ukraine and ultimately being forced back by the Russian winter and Siberian reinforcements.
There seems to be some merit to this claim, considering that even after capturing Ukraine, the Panzer divisions were said to be within binocular distance of Moscow (about 20 miles). Some claim that if they had had an additional few months, they could have steamrolled Russian central command before the Russian winter or reinforcements from East of the Urals could have arrived.
Hitler's main motivation for prioritizing Ukraine and the oil fields over Moscow seems to be his desire to avoid repeating Napolean's defeat and eventual retreat despite capturing Moscow. With the benefit of hindsight, would it have really made a difference? (i.e. would he have been forced to give back Moscow if he hadn't taken Ukraine?)
TL;DR: NO
There seems to be some merit to this claim, considering that even after capturing Ukraine, the Panzer divisions were said to be within binocular distance of Moscow (about 20 miles). Some claim that if they had had an additional few months, they could have steamrolled Russian central command before the Russian winter or reinforcements from East of the Urals could have arrived.
They were not in binocular distance of Moscow. Army Group Center was in very rough shape, with the infantry of the 4th, 9th, and 2nd Armies struggling to keep up with the 2nd and 3rd Panzer Groups. This got them in trouble east of Smolensk, when Soviet counterattacks badly mauled the panzer divisions, and the situation of Army Group Center was only to grow worse when the Red Army began launching a series of blistering counter-attacks in August, which forced back the 4th and 9th Armies and led to the abandonment of the Yelnya salient.
At the same time, Army Group South had had it rough since day one; Stalin had counted on a German offensive into Ukraine, and Mikhail Kirponos' Southwestern Front had a large concentration of armoured forces, which ensured a bloody slogging match for AGS right up to Kiev and the Dnepr, achieving a minor encirclement at Uman. Likewise, the rough, forested and marshy terrain of the Baltic states, combined with the poor force structure of Panzer Group 4 (only two panzer corps) meant that AGN was bogged down on the Luga River defense line. If Army Group Center continued any further, not only would they be advancing with exhausted soldiers, worn out tanks, and shoestring logistics, they would also be pushing an exposed Salient into the Red Army's lines, leaving their vulnerable flanks open for attack.
Attacking Moscow, and not sending the Panzer Groups of AGC to support the wings (as had been planned once the Dvina-Dnepr Line was reached), was a recipe for disaster. Halder, Bock, Guderian and the rest were simply too short-sighted and conceited to accept that fact.
EDIT:
The chances of taking Moscow in August 1941 were slim, and sending the Panzer Groups of AGC north and south were the best options they had. By the time of October, 1941 with Operation Typhoon, the chances of taking Moscow were even less, especially in light of the persistent logistical problems faced by AGC, and in light of the bloody fighting around Vyazma and Bryansk. With the operational pause in early November, the chances of capturing Moscow and winning the war in 1941 were next to none, but that didn't stop Hitler, the OKH and OKW, or Bock and Army Group Center from pressing on.
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