Here's an example of this from the first course in "Verycat Adventure". These jumps are already pretty tight as-is.
I have no idea if the author's intentions was to make it harder this way but given its described as having "vanilla difficulty in mind." I'm not entirely sure.
After playing so many custom SM64 levels I've noticed some creators like to add bevels around the tops of walls/platforms to make them smoother.
While it looks visually good this affects gameplay as you cannot easily ledge grab them.
Be careful with adding bevels!