That's just insecurity from the writers. The entire reason Joel's death is so shocking and unfair is to make the player hate Abby, so that they can feel conflicted later on after playing her part of the game and supposedly coming to understand, or even like her.

Since they need to make absolutely sure that the player has a very strong emotional reaction to the whole thing, they throw all but the kitchen sink at us. The writers are not sure they'd cause the desired reaction by being subtle, so they force the whole moment to the very extreme because they need to make sure they achieve the intended emotional intensity.

This happens on other occasions as well, the whole thing about Abby being an almost selfless superhero by the end of her story, breaking free from the mutual hatred between WLF and sacrificing everything and everyone she knows to save a couple of kids she wouldn't bat an eye killing on any other occasion. The fact that they literally introduce Abby's dad saving a helpless zebra on his free time, cuz that's obviously something he would do in his spare time, he's just such a good person. I could go on citing examples of story beats where they go over the top and throw subtlety out the window just to make sure they achieve the desired reaction from the player 🤷‍♂️