I see online people celebrating his death and this is bad. He was a bad person, probably even evil. But nobody deserves death wishes or the death being celebrating.
Tell that to everyone who popped open champagne when Fred Phelps bit the dust.
Or Hitler, Stalin, Osama bin Laden, Jerry Falwell, Bernie Madoff, and every other tyrant, murderer, rapist, abuser, bigot, crook, and other miscellaneous asshole hell-bent on making other people's lives miserable for their own personal gain.
There are people out there that are sufficiently evil to where I can understand why people celebrate their deaths. Sugiyama being a war crimes denialist and general bigot is arguably enough to qualify. It goes to show you that just because someone is talented and creative and contributes a lot to society it doesn't mean they can't be an awful person. I'm all for "separating the art from the artist" and not burying the cultural contributions of bad people, but a bad person is a bad person and should be viewed as such regardless of their contributions.