I think I was a little confused as to what you meant before, do you mean the blue light could be a scrollbar? I don't know, although the cooking menu also doesn't have anything that looks like a scrollbar or indicates multiple pages now that I'm looking at it. They said you get more recipes from visiting dining halls, maybe the fabricators just give you gem recipes. Then as recipes get added, the gem menu will add a scrollbar somewhere.
The machine looks interactable, it's got an icon on the map and everything just like containers, flutes, and ether channels. It's a little unclear where the embargo ended exactly. It seemed like it was supposed to end at chapter 1 with the Wild Ride fight but we've also seen plenty of footage with the previewers running around Millick Meadows at the beginning of chapter 2, and they were allowed to discuss classes which is a chapter 2 thing. It's possible Nintenduo just showed a little more than they were supposed to. I've also seen those purple vines in the preview videos that are confirmed by the blog to be a field skill thing even though previewers said they never encounter field skill checks.
The machine is at 3:30 in this video, it has that circular glass pane reminiscent of gem-crafting/aux-core crafting furnaces and I have no idea what else it could be (be warned: this is one of the more spoilery previews for anyone who was avoiding stuff)