I think fear of cassowaries is unjustified. Their sort of tropical coloration and dinosaur like casque make them seem more menacing than they really are. The only confirmed human fatalities are from a guy in Florida who was keeping one in a pen, and two Australians who tried to beat one to death with sticks. In both cases, the cassowary felt cornered and chose fight over flight.

Overall the cassowary probably is less dangerous than other fauna about the same size like eurasian boar, though I can't prove it. It's just territorial and defensive of its eggs like many other bird species, just because it's equipped to kill doesn't mean it's violent.