Let me do my best to address your points:
- The syntax
The syntax I used is lambda calculus; lambda calculus consists of a language of lambda terms, which is defined by a certain formal syntax, and a set of transformation rules, which allow manipulation of the lambda terms.
You can find more information here https://en.wikipedia.org/wiki/Lambda_calculus#Notation
2. PHP and NonSQL
While true that the data model is important, I think you are missing the point; PHP cannot scale at the same rate or with the same ease that some FP languages can, one of the things that made WhatsAPP unique and so attractive for investors is the fact they are able do more with less resources (people, teams, etc)
3) Imperative Languages
Sure C++, there is also LISP if we want to go further back in time; the point; again not sure what you are trying to clarify with that statement? There are other languages and concurrent programming is not a new concept, we agree on that; the point that I was trying to make with the article is that FP (due to a combination of factors) is now becoming a more attractive option, and a better fit for the next generation of web applications. My bet is that we will a raise in demand and dominance of Functional Programming languages in the next 5years.
4) Right tool for the job
We are not in disagreement here.