Its no huge surprise that spreadsheets implement a form of FRP . Specifically, you can look at loeb's function [1] as an example of the relation. Being able to focus on the data itself while easily composing operations is definitely functional in nature.

However, FP is not a silver bullet either. In practice I think humans care a bit less about correctness than compilers and would like some aspects of the language to be 'fuzzy' for lack of a better word. To most people "1" and 1 are the same thing so why shouldn't the compiler understand that. There could be potential for a dynamic-fp language of sorts.

[1] http://blog.sigfpe.com/2006/11/from-l-theorem-to-spreadsheet...