Mostly, I've always hated stories that were dumbed-down for kids, even when I was a kid I knew it was not supposed to work that way.
I really find it stretches believability when no one ever dies in a crisis situation, especially if the justification is extremely contrived or totally absent.
I'm not talking about Wil.e Coyote surviving anything - that's obviously not meant to be taken seriously, I'm talking for example about Star Wars Resistance, when nobody dies in a whole season against all odds (and then a whole planet blows up because it connects with the main story!) or Kirk being conveniently resurrected at the end of ITTD in a way that should have really wide implications but is totally forgotten elsewhere.
Also, I believe that a child should have a chance to accustom themselves to the concept by being introduced early to the idea, not have to cope with it when a beloved grandparent dies. But then I never found that lying to a child saying "he's gone to a better place" was a particularly good idea.
This is another question whatsoever. I think she should be killed off if and only if it serves the story, not just because. This is why I understand Icheb dying in Picard (I didn't particularly appreciate the graphic way it was depicted, but it worked within the story) but hated how they killed off Hugh, feeling they wasted him for no real reason.