There is no doubt that Hitler was one of the evilest human beings ever to walk the earth.
But, Let's be a bit objective and look at the degree of Hitler's evilness in a balanced perspective.
Hitler the person:
Of the major leaders during WW2, Hitler was the most disciplined and cleanest-living. Unlike Churchill, Roosevelt, And Stalin, Hitler was a strict vegetarian, rarely drank and did not smoke.
He was not anti-Semitic by nature as illustrated by his close relationship with his mentor, a Jew, during Hitler's early years as a budding artist.
Although his "autobiography" outlines extreme anti-racist views, Mein Kampf was mostly written by Rudolph Hess since Hitler was largely illiterate, or most likely, dyslexic. Anti-Semitism was rife throughout Germany at the time and it would be fair to say that a politically ambitious Hitler played the anti-Jew card to gain votes.
It could also be argued that Hitler felt uncomfortable with the "Final Solution" having absolved his responsibility to Heinrich Himmler and Adolf Eichmann.
I'm not in any way trying to infer that Hitler was any less evil than we know him to have been since, after all, he was the leader of an organization that committed some of the most appalling atrocities ever committed against mankind.
But, let's compare Hitler's evil with the sort of evil that still continues in the form of a small but ugly undercurrent of hatred and bigotry in modern society.
Hitler had reasoning (albeit flawed) for declaring hatred against minority groups. Yet there are unsavory individuals who declare hatred towards others for absolutely no reason at all other than that they are inherently ignorant and arrogant. Sure, these low-lives are eager to publicly utter what they call "reasons" for their extreme anti-social behavior (e.g., "homosexuality is unnatural"or "it is written") but they are no more than flimsy and insulting excuses.
Are we entitled to label these pathetic, cowardly non-entities eviler than Hitler?