From a standpoint of industrial production, that's true. But the fighting and dying still needed to be done. And also keep the Soviets in the war, tying down the Wehrmacht. I don't believe it was a foregone conclusion, and it took the Allies holding to the unconditional surrender demand that prevented some kind of other peace, which would have probably led to another big war in the future. Plus, to win it quickly enough to keep the Germans from developing the bomb and other advanced weapons. They did manage very limited production of jet aircraft. And if they had been able to attach more lethal warheads to the V-2....
Well, granted, inevitable is a pretty big word. And lots of stuff had to happen. But mainly, the three big powers were going to prevail if they just didn’t screw up too badly.
Hanson addresses German weapons and the Allies’ coordinated war planning. I think you would find his comments interesting as to the cost/benefit trade offs of big tanks, big ships, the V-2, etc.
VDH is a gem of an analyst and instructor. I urge you to watch the videos from Hillsdale. Each is about 45-55 minutes long and quite watchable. (If that’s even a word, LOL).