Even if it's a tech demo, the glove is meaningless unless it's overall position is also tracked because sign language isn't just the spelling out of words with individual letters. Gestures possibly involving both hands are used to convey complete ideas or concepts. Hands with palms together and fingers together, put against the side of your head, tilt your head, means sleep. Will a simple glove be enough to pick that up?
Being in Chile, maybe they have their own Chilean Sign Language and not the codified American Sign Language (ASL) so idk if things are easier or harder, I imagine a glove just not being enough.