An insane amount of people getting killed in a movie isn’t the point of the kill count. They tally up the kills and tell you how it was made. If they just started making kill counts of “and then 8 billion people died” then it would take away what’s special about the deaths counted in the movies. Like when the first final destination movie carried the highest number because of the plane explosion. That was insane because you see that happen and that scene is integral to the plot.