I really don't understand why people don't just scroll on by if they don't like it or understand it
Not commenting on the veracity or otherwise of the Claire threads. However, as a matter of principle, claiming that your child is dead - if untrue - would cross a line. There are many MNetters who have lost children IRL. It's not as simple as just ignoring the threads because they appear in Trending and Active, and people may click on them without knowing what to expect.
No one wants to deny a grieving person support but, equally, bereaved parents should be protected - as far as possible - from trolling and attention-seekers.