Of course, it did not help that Hitler thought he could advance much faster and did not even prepare for winter. Those two winters weakened the Germans significantly.
Here's some scientific evidence of the Russians throwing over 20 million human lifes [1] into german gun barrels: take a look at the original post. You mentioning the winter twice seems quite cynical in context.
[1] I've recently read a newish book about the casualties on the eastern front which suggests (based on research by western scholars) that the actual numbers were probably well over 32 million people and due to political reasons had been down played a lot by soviet sources.
My father was in the Finnish army (which suffered too small losses to even fit in the presentation) fighting the Soviets, and was wounded in a Russian counter-attack north of Petrozavodsk in October 1942. The battle diary of his brigade says "we suffered bad losses".
A Russian division-strength attacking force pushed a Finnish brigade-strength force back about 400 m on a fraction of the front which was about 800 m wide.
The "bad losses" were 49 men killed on the Finnish side. The Russian losses in this two-day battle were estimated about 1400 men killed. And as a result the Finnish commander remarked that "the Russians have changed; they are no longer throwing human life away completely mindlessly and they actually try some sensible military attack tactics".
A ratio of 30 Russians killed in attack to grind down 1 enemy was "sensible" compared to what the Russians had been doing before that. Of course, eventually it worked, they had the 31st soldier as well.
Battle of Kursk was fight in the summer, Stalingrad was fought over multiple seasons. The most major factor that winter played was probably Moscow in 1941.
From the diary of Otto Geipel: “1942: The winter comes with full strength, hardly a way left to advance without missing winter equipment. Even the winter clothing is missing. (. . .) At midnight the temperature dropped to a new reported low point. On 24 January 1942, –56 °C was measured at our division observation post.”
Weather conditions like this make a difference and lower the dynamics of the war. Strategically, there are more factors like supply lines, wrong strategic decisions, and an industrial complex that us sufficient enough to regenerate the losses [1].
My point was that the siege of Leningrad took a year and a half. The 'Russian Winter' doesn't exist in summer. Clearly it was more than 'basically the Russian winter' that stopped the Germans, especially since the German war machine was proven able to take out heavyweights like France in only 6 weeks.
No-one doubts that the Russian winters were a significant factor, but your original statement pandering to mythology, not fact. Russians were throwing themselves into a meat-grinder to stop the Germans - at Stalingrad, the average life expectancy of a newly-arrived soldier was 1 day, and for an officer it was 3 days. Writing off that kind of sacrifice as "nah, basically it was the winter that did it" is living in a fantasy world.
