If JavaScript never goes away and no other options are built into the web browser, the web will become irrelevant within 10-15 years.

No language lasts forever (especially not one that evolves as slowly as Javascript does), and tying the web to JavaScript and JavaScript only very obviously dooms the web. Not this year or three years from now, but eventually.

That nobody other than Google is making long-view plans for the future in this regard is somewhat insane.