Remember that, unlike real life, in fiction writers have a choice. Far too often writers with a lack of imagination use death as drama when it is really just an easy way out, or to piss on a franchise to "leave their mark" on it like a dog to satify their ego, or simply to lazily manipulate the reader or viewer. Sometimes it's because the actor has become too expensive or too annoying. The real Universe is much more objective about it and does not kill people because of those things even when we wish it would.
Sounds like you're talking about something very different than the OP.
Not at all. Fictional death is easy to write with just a stroke of the pen or a press of the keyboard. Who cares? It's not real. So pile on the numbers of deaths for greater drama, right?
Consider these quotes:
Mr. Spock said:
I've noticed that about your people, Doctor. You find it easier to understand the death of one than the death of a million. You speak about the objective hardness of the Vulcan heart, yet how little room there seems to be in yours.
So just rack up the body count for shock and awe to increase the drama because one just isn't enough.
The Wiki said:
The death of Tucker was another object of controversy. Salem described the development as "a major character is pointlessly killed off in service of a pointless plot device," a complaint echoed by IGN. Actor Connor Trinneer, who played Trip, said during a convention appearance that the character had "gotten out of much worse scrapes than that," and the death seemed forced. The writers, Trinneer contended, wanted to kill off a character to "get the fans talking," and so Trip was killed off simply to manipulate viewers.
Fictional death is easy to write, so writers all too often use it for impact and manipulation rather than doing something organic with the character that requires more effort - building drama without death. So the excesses of death in a fictional show may reflect the writer's lack of imagination and result in an increased body count and often the typical ratings ploy in promotional ads that offer up the sacrifice of "A major character will die!!!!!." Yes, I'm sorry, but this does suggest that even Star Trek writers get lazy sometimes.
Just so you know, I do not count Spock's death in "The Wrath of Khan" as one of these cheap deaths. It was organic, part of the story and character, and was meaningful. Contrast that to Kirk's second death in "Generations." That was about pissing on the franchise where the conversation starts with "Let's kill Kirk!" instead of at least allowing the character and plot to lead them there.
Before anyone brings it up, as I recall it, the story goes that they attracted Nimoy back to the role of Spock in "The Wrath of Khan" by telling him "We'll kill Spock" in addition to offering the role of Golda's husband in "A Woman Called Golda." But as the writing of "The Wrath of Khan" went on, they pushed Spock's death further towards the end because that's where the story lead them.