I now feel like how the Eastern Front was presented to me - as rapid German gains meeting the harsh winter - was some sort of pro-German or anti-Soviet bias during (and after) the Cold War, rather than what actually happened.

Here's why; I was reading a Squadron book (so all about the tech, no actual historical analysis) about three similar German self propelled guns, developed and rushed into production in 1942 to meet challenges - long range artillery, lack of armored close in fire support, difficulty transporting heavy 8.8 cm guns without roads. For reference Barbarossa started in June 1941, and T-34s started production in 1940. Reading between the lines here gets me "they screwed up thinking it would be a repeat of the 1940 offensives" and "they ran into significant and possibly very intelligently led resistance beyond just mud and cold weather."

(It gets better. Tiger tanks started rolling out in August '42, Nashorn tank destroyers date from October '42, which plays into the "what you've been told about Tigers being ultra super fantastic is basically Wehrmacht fanboying if they needed a *different* way to get 8.8 cm guns to the front.")