> In some sense, it is, it's just happening every slowly.

Yup, real world engineering doesn't heed purity of concept. What you get is a hodgepodge of best practices and ideas that work. Today we see JS, Golang, Ruby, modern C, C++, all of these things have ideas and features directly drawn from functional programming and likewise, many functional programming languages use ideas from other paradigms.

We likely won't see Lisp or Smalltalk become dominant anytime soon but there is no denying that many of their features have made it into many of the main stream languages that have become mainstream for reasons far detached from their programming paradigms (um maybe not Java, for better or worse, Java sold OOD and OOD sold Java).