Fine. I'll rip it apart point-by-point then.
This right here is a false analogy. What is being described above is a clash of different cultural norms, but Voldemort has not been raised in a different culture. He has been raised in Britain, experiencing both the Muggle and Magical sides of that country, and there is no cultural gulf between him and any half-blood or Muggle born magic user. What drives Voldemort's war against the Ministry and wider Magical Britain is personal ambition (to be the most powerful wizard ever and to live forever) cloaked in an ideological agenda. (pure-blood supremacy and genocide of Muggle-born wizards)Say there is this tribe in Borneo who believes that you should only wipe your butt on a tree trunk, to use your hand is evil. You're thinking that using your hand works perfectly fine for wiping your butt and it's not evil at all. Evil in this case is relative to the beholder. The tribe thinks we're evil and we think they are silly.
There is no evidence in the books that anyone knew Tom Riddle was a Parselmouth during his time at Hogwarts. You completely overlook that Tom Riddle was well liked and admired by the Hogwarts staff and his fellow students. He was Head Boy and when it came down to his word vs Hagrid's, Professor Dippit sided with Riddle without second thought. Tom Riddle's his reaction to Dumbledore telling him it's a trait is telling. He's happy. It's a trait that makes him special; better than other wizards. It feeds his ego and belief that he is superior than others.Voldemort cavorts with snakes. Not his fault as he was born with an affinity to snakes and can speak their language. Sure the snake is a symbol of evil in Christianity, but the animal could've been a crow just as easily.
Gun powder and TNT have uses besides destruction. Most notability in blasting for construction. What was the forbidden knowledge Voldemort got from the library? The Horcrux. A way to place a part of your soul into a container. How does one make a Horcrux? Murder. There is no other way. It is ultimately a selfish spell. Rob another of life so that you may live past death, but the side effects are clearly negative. Rip your soul asunder and more you dehumanize yourself physicality, emotionally, and with possibility of getting trapped in the limbo between life and death. He does not expose this knowledge either, "only I can live forever," as he said before murdering Snape.Voldemort researched forbidden knowledge in the library's restricted section. Forbidding technology is silly. Would you restrict the knowledge of gun powder? Did Noble restrict the knowledge of TNT? No, he made millions of dollars off of it. Who get's to call knowledge "restricted"? Didn't Voldemort do a service by exposing forbidden knowledge?
The most powerful Dark Wizard ever known has started a war where Lily Potter (Muggle-born witch) is a target of his genocide campaign? Along with her baby son and all how oppose him? I hardly see the grey when the aggressor of a war of conquest is doing so for purely personal gain.Voldemort killed Harry Potter's parents. Well, they were trying to kill him.
The point here is undermined by Dumbledore very pointedly not fighting to kill during their duel in the Ministry.Voldemort plotted the death of Dumbledore. True but Dumbledore was plotting the death of Voldemort.
Different how? While a student at Hogwarts Tom Riddle was well liked by the Hogwarts staff and admired by his fellow students. He became Head Boy and many thought he would go onto great things. He even won an award for "solving" the murder of Moaning Myrtle. This was all an act that only Dumbledore saw through because of their first meeting. The glimpses we see of him at Hogwarts all scream sociopath. He already divorces himself from the common name of Tom for Voldemort and gathers a group of thugs around him that go onto be the first Death Eaters. He only ever lets the mask slip while talking to Slughorn. As he presses him for the secrets for immorality.Voldemort was different. If we kill everyone who is different, we're in for a long day.
The reasons are rather clear. Rule Magical Britain. What does he do when he topples the Ministry and places his puppets in control? He installs a ranking based on one's blood purely. The imprisoning and torturing Muggle-born magic users and the creation of a surveillance state that closely watches the movements of those pure-bloods that might not be loyal to him.Voldemort caused a war and people died. People die in war all the time. Voldemort might've had reasons to declare a war.
Hitler and Nazi racial ideologically are what Voldemort and his Death Eaters are based on. The half-blood wizard (Jew) who in his colossal delusion, ego, and self-loathing wages a war of annihilation against those he perceives as inferior. A personal guard (Death Eaters: SS) that can trace the purity of their racial linage back generations. Who seizes control of the weak government (Weimar: Ministry) and imposes a tyrannical regime.I think using a fictional well know character like Voldemort is better than using someone like Hitler cause Hitler carries a lot of emotional baggage.