Good read by Douglas Porch - “The Path To Victory, The Mediterrenean Theater in World War II”. Makes the case that while the Germans couldn’t win the war in the Med, the Allies most surely could have lost it if they hadn’t vigorously contested them there.
Soviets not fighting competently is an understatement. Something like 88% of the male cohort born in 1922 in Soviet Union and over 50% for several years on either side died in the conflict. It was the direct cause of the emergence of the steriotypical spinster “Babushka” women, unable to find husbands in that age group after the war.
Sheer manpower was their greatest resource, and at war's end, it was the Russians standing in Berlin.
Incidentally, I just listened to a podcast of a BBC Radio documentary about Russians who go into the forests and locate the skeletons of soldiers who were never buried. After the war, rather than recover the bodies, the Russians would plow the area and then plant trees, frequently directly on top of the remains. And even now they're senstive about it, with Putin torn between recognizing these people and trying to restrict their activities. They told the story of one soldier they were able to identify and how the family was told that he was missing, thought to have deserted, and they were denied survivor benefits, apparently a very common story.