I fail to see how they relate...? Prank videos often show what some might consider harassment of strangers. SCPs are essentially a collection of creative writing prompts. I legitimately cannot fathom how the existence of the SCP website would bother someone unless they just have an issue with fiction writing for some strange reason...?
Considering the Fediverse is new territory, legally speaking, I can sympathize with a bit of extra caution from instance hosts who don't have a team of lawyers backing them up.
There's nothing in that playground you couldn't find in a typical American playground. The Americans you know apparently just have the personalities of wet towels.
Welp, you definitely don't know how to drive...