I'd think if they had a product they'd actually demonstrate it in the video, instead of showing some fakery and then the inert product.

From what it looks like, the founders didn't submit it to HN. For all we know, this page was thrown together as somewhere they can direct people who ask them what they are working on, not somewhere they are actively trying to drum up interest with (if they had nothing beyond what the page shows, my guess is they would have gone with a Kickstarter, rather than just an email capture).