I've read a lot of WWII history. Especially focused on the ETO and Germany. In my mind, it seems beyond clear that Hitler was the reason that war broke out, the single prime key motivating force, his desires, his influence, his decisions, his cult of personality, his charisma, his quirks, his obsessions, etc. He existed and acted within a framework of other facts, within a certain context, and there were plenty of others who failed to act against him, enough, early enough, when it would have been more effective. But I've been confident of the "because Hitler" idea for a long time.
If you can point me at a history book or analysis which you think contradicts that, definitely share it with me, I always love to learn different angles. If I were to give you just one that aligns with "because Hitler" I'd recommend Shirer's Rise & Fall.
I'd therefore assumed that Hitler was just a product of the era and there was a certain inevitability to WWII.
I've never been a fan of the "great man" view of history -- easy to teach but barely illustrative -- but there is no question our actions have consequences. The importance of taking the large view is that you can see the larger forces that someone can harness (or that can thwart them). But the claim "if not Julius/Napoleon/Hitler than someone else" is at best hard to prove -- what someone else did would have been quite different. Most likely it would instead have been the usual muddle -- the default state is muddle, with from time to time some demagogue able to weave some strands together and cause general excitement.
This is no different from, say, science. What would Newton have done had he been born 100 years later, or earlier, or 1000 miles east? On the other hand it's easy to see that if he'd not been born we'd have much of the same physics as today.
The former goal failed thanks to the Soviets putting up a good fight, the huge size of Russia, and bad weather. The latter because Hitler really wanted to defeat the Soviets at a city named after Stalin instead of just driving past it. He wasted his entire invasion force (~800,000 casualties) when the Soviets encircled and destroyed it.
The Soviet commander in charge of the defense of Stalingrad, Zhukov, escaped Stalin's purges because he was stationed in the middle of nowhere, and soundly defeated the Japanese in Mongolia when they tried to invade in 1939. Japan gave up it's plans to invade the USSR for resources (permanently, as communicated by the spy Sorge, which allowed USSR to transfer all of their soldiers to the European front), and instead invade European colonies instead, which directly led to Pearl Harbor.
WRT Japan, this was called an embargo in response to the Rape of Nanking.
Building on your point about WWII being economy Vs economy and the economic underpinnings of the war in the Pacific, I have a memory of reading a similarly economics-centric analysis of the start of the war in Europe. I do not have a link but from memory Germany had insufficient farmland relative to its population and little access to important resources, especially oil. This set them up to be dependent on their neighbors indefinitely, neighbors who could turn off the food/oil tap at any time. That was not an appealing idea to the Nazis.
Not sure how well accepted that theory is or isn't but it certainly seems to hold a lot more credence than "the war in Europe started because Hitler."