In truth, green didn't completely die. Some aspects of it became so ubiquitous that they vanished from view. Many products today use less packaging, less embodied energy and fewer nasty chemicals than they did a decade ago. They just don't shout about it so much. Green became normal.
But green's message did not adapt and it ran out of steam. It fell foul of the law of diminishing returns: it's easy to make the first cut in your carbon footprint, but every subsequent one gets more difficult. And because the back-to-nature, made-do-and-mend doctrine supped from a limited gene pool of visual stimulus, it became an aesthetic trap. Once you've hewn furniture from raw timber, there's not much further you can go.
Technology however is intrinsically optimistic: each new development, each new device brings the promise of a new future. Each new way of arranging atoms or bits opens the door to a new solution cloaked in a new form. And since these elements are infinitely configurable, technological development is more sustainable than sustainability, since it will never run out of ideas.