I think the problem was sooner the way the war ended than the peace terms agreed upon. The war didn't penetrate German borders; the German military was not 'thoroughly' defeated (though, really, it was not going to put up much resistance in October 1918 given the state it was in). This meant that whilst ordinary Germans had verifiably endured great hardships during the war, it wasn't clear to them that they had actually lost the war: hence the 'stab in the back'. Contrast this with 1945, when the bitterness of defeat became incredibly clear to Germans.

This didn't make Nazism or WW2 inevitable, but it created the situation in which the Right could tell the tale of a strong, proud Germany, on the verge of victory, being fucked over by socialists hell-bent on ruining the country. Versailles was just part of this myth.