Erm, Lisps were used back in time for many production systems when C++ wasn't even started. Looks like your definition of esoteric and production is based on couple of years of cheap CS courses.
Oxford's definition of esoteric: "intended for or likely to be understood by only a small number of people with a specialized knowledge or interest."
Today, C++ is a dominant programming language. Lisp is only used in niche applications. Therefore, it is likely only to be understood by a small number of people with specialized knowledge -- hence, it is esoteric.
Upon conception it was neither "intended" nor "likely" "to be understood by only a small number of people with a specialized knowledge or interest" and it is still not intended that way nor likely, that only few people _can_ understand it. It is just that people choose not to take time and understand it.
I don't agree with the conclusion you draw from a definition of esoteric, that is without context anyway, taken from a natural language dictionary.
