I think Excel language is great: It's fantastic that so many people in the world are unwittingly gaining experience in using a pure functional language, and its conciseness really lends itself to writing in relatively small cells. There are no side effects, it's hard to shoot yourself in the foot.

I do find myself writing fold-like functions by creating a column to hold the accumulator; whereas it might be nice to have that syntax built-in.

It's an intuitive functional language. Well played.