1000 years ago, the primary frontend toolchains were singleton and handmade: every instance of a piece of data needed to be individually crafted.
500 years ago, the printing press had made significant changes, but frontends were still largely coupled to the available presses and their character sets (let alone niceties like layout and graphics).
100 years ago, frontends still remained tied to their physical layers (ie, it wasn't possible to scrape data and create a new frontend without recreating the entire medium) - ie, books and magazines and newspapers.
20 years ago, javascript was barely known even in programming circles, much less a lingua franca for publishing worldwide.
Today, javascript is the control structure by which the vast majority of data is accessed by human eyes and ears.
In 20 years, something that has already been invented but is today not largely known might well be responsible for most knowledge exchange. It's completely plausible that technologies like AR, crypto-blockchains, and newly legalized psychedelic drugs will be as important as HTTPS is today for transmission purposes, let alone the particularities of the application layer.
100 years from now, it's highly unlikely that the screen-and-keyboard model of data ingestion will be regarded as anything but a historically important link in data evolution, cast away in favor of more tactile, neurochemical, and cybernetic interfaces.
500 years from now, most of the world's governments, media traditions, and spoken dialects of language will have folded and made way for a completely new condition of humanity. Who knows what the frontend will look like.
In a 1000 years, our species might plausibly have no biological footprint (ie, no sensory organs to use for the purposes of distinguishing "frontend" from "backend") whatsoever, and live on as information and knowledge, present in the physical universe only in ways that we can't possible yet imagine.
So yes, the species will someday move away from javascript.