It’s because when you’re dead you can’t defend yourself.

But mostly it’s to protect the feelings of the living.

I think it works on a small scale when people who knew the asshole are still mourning, but breaks down when we're talking about public figures who affect policy.

Also if they were demonstrably an enemy to human decency imo

I've always heard it as don't speak ill of the dead at the funeral. Or wake or what have you I guess. Certainly it's never been forever.

Many years ago my parents had a neighbor. He was a nice guy but annoying as all hell at times, so much so that my mom purposely avoided him at the pool. If she saw him she'd go out of her way to walk around to the side of the pool and be sure to not get in the water when he was in there. She spent months not being able to say 1 remotely decent thing about him.

Then he died unexpectedly of a heart attack. And suddenly he was the nicest person she knew, always so friendly and loved chatting with him, etc etc. I straight up called her out on it.

I think it's more of a "don't hold onto hatred" kinda thing. They're dead, so let it go for your own sake, as well as those grieving. It doesn't help anyone

I don't think it applies to public figures though... At least not if their family isn't around. Hell, I think it's just fine to celebrate the world becoming a better place

I don't let hatred build up in myself, but I sure as hell have felt hope when I see some monsters have gone

From my understanding, it's more of a tradition, or a rule of thumb, than a capital offense.

Kind of a way of saying well: that's that.

I don't think you're supposed to white wash assholes, just don't marinate in it now that it's less important.

Of course, you don't denigrate yourself or others for the dead, but carrying their water would be real dumb too.