The cause here is WWI, not the great depression.
Huh? Your reading comprehension needs some work. This is a list of causes of the Great Depression. Of course the Great Depression is not a cause of the Great Depression. The first cause of the Great Depression in the list is... (drum roll, please): the effects of the gold standard!!!
abandoning the gold standard because of war
Hmmmmmmmmmmmmmmmmmmmmmm what about war causes deflationary currency to be unsuitable? 🤔🤔🤔🤔🤔 And are those conditions exclusive to war? Checkmate. That was easy!