If all of the ``functional programming'' programs that ever existed disappeared, nobody would notice except for the people who work on ``functional programming'' compilers.
If all of the imperative programs that ever existed disappeared, there would be no more programs, including critical parts of ``functional programming'' software.
Alonzo Church invented the lambda calculus in the 1930s, originally to provide a new and simpler basis for mathematics.[1][2] However soon after inventing it major logic problems were identified with the definition of the lambda abstraction: The Kleene–Rosser paradox is an implementation of Richard's paradox in the lambda calculus.[3] Haskell Curry found that the key step in this paradox could be used to implement the simpler Curry's paradox. The existence of these paradoxes meant that the lambda calculus could not be both consistent and complete as a deductive system.[4]
This was the original reason for lambda calculus. It was a failure there too, but it's still useful as a money sink for getting grants. Every time they ``patch'' lambda calculus to solve some problem that normal math already solves, it gets more and more complicated.
Can anyone honestly say homotopy type theory (or whatever the latest version is called) is a ``simpler basis for mathematics'' than set theory?