You... you must have been quite some 5 year old.

Lol. Def not for 5 year olds but it's about exactly what I needed

How about this:

Take a lot of pictures of a scene from different angles, do some crazy math, and then you can later pretend to zoom and pan the camera around however you want

ELI5 has meant friendly simplified explanations (not responses aimed at literal five-year-olds) since forever, at least on the subreddit where the concept originated.

Now, perhaps referring to differentiability isn't layperson-accessible, but this is HN after all. I found it to be the perfect degree of simplification personally.

Some things would be literally impossible to properly explain to a 5 year old.