I'd say historical deaths that are basically just parts of the backgrounds of the characters can't really be counted as those deaths DE was talking about. But yeah, there are some lone deaths in One Piece. I can't immediately think of any in Bleach (manga based)... Hollows are abnormal beings and, according to the shinigami propaganda, are more like freed by the shinigami than killed.

I also wish people would die in Bleach. It was just the kind of series that would have been even better if those seemingly killed people of the SS arc would have stayed dead.