Why Colby's Death In Yellowstone Season 5, Episode 12 Is More Heartbreaking?

In Yellowstone season 5, episode 12, "Counting Coup," the ranch lost another character, although this time, their demise felt very different from the killings of Sarah Atwood and John Dutton III earlier in the season. Season 5 of the neo-Western drama on the Paramount Network is slated to be the final season, presumably ending the series in 2024. Even though their deaths don't make sense in terms of the plot, it feels like everyone's life is up for grabs given how much devastation has already occurred in Yellowstone season 5, part 2.
Because it seemed too good to be true, the opening sequence in Yellowstone season 5, episode 12 might have warned viewers about Colby's demise. During their phone conversation at the top of the hour, Colby unintentionally revealed his love for Teeter. Teeter wouldn't let him get away with it, even when he tried to retract it by saying it was too early. Unaware that it would be her final conversation with Colby, Teeter assured him she loved him too before hanging up. Colby's death was therefore all the more terrible.

TV shows should never do something out of the ordinary solely to surprise the audience; instead, they should startle them with unexpected plot points that make sense. For instance, the startling death of Sarah in Yellowstone season 5, episode 11, advanced the plot. Nevertheless, despite being shocking and devastating, Colby's passing added little to the narrative beyond upsetting the other characters. John was already dead on the Yellowstone Dutton Ranch. Was it really necessary for the characters in Yellowstone season five to lose Colby as well?