Original article author here.
One of the interesting things about the lambda calculus is its universality: by itself, it's a complete foundation for computation.
Here's a different old post of mine showing how to build the rest of the programming language, all in a miniscule subset of Python that is the pure lambda calculus:
https://matt.might.net/articles/python-church-y-combinator/
You can even extract recursion out of the Y combinator or the more primitive U combinator -- out of nothing but lambdas!
So, it's lambdas all the way down.
Another interesting thing about the lambda calculus is that it wasn't intended to be a programming language. When Alonzo Church created it, there were no computers to program.
Alonzo Church was trying to solve problems in the foundations of mathematics.
But, untyped lambda calculus has a "bug" that makes it problematic for mathematics -- the self application that enables recursion is a problem if you're a logician who cares about soundness, but it's fantastic if you're a programmer.
I don't think of functional languages as obfuscating. I think of them as terse and expressive. They let me most directly encode the model in my head as running code.