Saying that the Treaty of Versailles placed all the "war guilt" on Germany is a common notion, but you might want to see "What is the reasoning behind blaming Germany for WW1?" by /u/DuxBelisarius .

But this is not to discourage discussion -- further questions, data, and debate are welcome.

It is worth looking at the state of affairs for the world powers at the end of the war. Russia was out thanks to the October Revolution, leaving France and Great Britain as the remaining Entente Powers. Both of these powers had primarily faced the German Empire and the German Empire was responsible for the vast majority of their losses (I know both countries also faced Ottoman and AH forces on other fronts but the Western Front was responsible for the greatest number of losses). The German declaration of war on Russia was also the reason that France was drawn into the war and the German invasion of Belgium was the Cassus Belli for Britain’s entry into the war. German unrestricted submarine warfare and attempts to draw Mexico into the war also pulled the US into the conflict.

So three of the four major Allied Powers were directly drawn into the war by Germany and it was those three powers that drafted the terms of the Treaty of Versailles. It is not surprising then that Germany, bore the brunt of Allied judgement after the war.