Per TFA, this is a highly manual one off process with a not-well-scaled resource - a specific type of vine cutting that can only be harvested every other year without affecting the overall vibe health.

So Id wager it's the brutal road from proof of concept to scaled production.

That's a kind way to put it. I'd call it a shit idea that produced a paper for someone's CV.

Do the same with bamboo, HFCS waste, or something similar in availability? Now you're talking!