“Hitler came to power because of the Depression’s effects”
The depression was necessary but not sufficient.
“The infamous ‘stab in the back’ theory was sown by Hitler and Co”
Wrong. It was formulated immediately and pretty widespread.
“Most Germans had more important things on their minds than revenge for WW1.”
They probably had other things on their mind than whether Hitler was the man to cure the depression, too. He was just a guy from a marginal party who happened to be appointed chancellor in a counrty that was ideologically fractured and tired of politics as usual.
The “stab in the back” was prevalent among german SOLDIERS after WW1, not nearly so much among civilians, who had had enough of war by that time.