Yeah, one aspect of the German military after the fall of France is how depleted they were both in manpower and hardware. Sure, they were still a powerful army, but nowhere near their full operational strength as defined in doctrine.

If Germany were able to magically reinforce up to full strength, the outcome could have been very different (on land at least. Navy was severely lacking in most respects, even before 1939). Their manufacturing were only barely able to compete with UK and her allies at the beginning of the war, let alone USSR and the US once they entered the war.

And manpower surges during the war came at the cost of industry. On a surface level it might seem like Germany was great at reducing unemployment and all that, but the truth is that it was an act of desperation - the war economy was bleeding Germany of any and all capable adult (and many who weren't even adult), and this is obviously not something that can be sustained in the long run. And especially concerning for russia these days is what happens when you try to turn a war economy into a civilian economy - It's going to be a disaster. War economy uncurs a massive debt, financially and otherwise, and one day that debt needs to be paid.