First, Javascript is diverse, for some it is ECMAscript, for others it is the interface for the V8 engine, for some others it Rhino or Nashorn. It means differe

First, Javascript is diverse, for some it is ECMAscript, for others it is the interface for the V8 engine, for some others it Rhino or Nashorn. It means different things to different people at the very fundamental level, not common for other popular languages. Next, it works well on the serverside for how sloppy that language is and is the ONLY language that will work in the browser. Thats a huuuuge edge. Futher, with npm and github, distributing js is free as in free beer. No one has a problem with free beer till it starts hurting. Also, no one got famously sued or slapped with a huge bill for using javascript without someone's permission. None of these is likely to change anytime soon. So my guess is it will keep evolving till it becomes boring and people move on, thats a decade or more away if I were to make a free, non-consequential, unsolicited speculation.