Godot is designed for making games and rendering Games at 30-60 fps, it does not include opinonated solutions for Desktop Apps and also skips accessibility. But for a simple, interactive kiosk app that runs in fullscreen it could work. Most of the time these interactive apps grow into complex animations, so using a game engine does not feel all that wrong.

The inspiration and artwork comes from QT Coffee Machine Example, the king of platform independent apps.

Demo of a coffee machine on the Raspberry Pi 4 2GB with 7 Zoll touchscreen. Audio is from the game Subnautica. With low processor usage mode it only used about 7% CPU. Exported build including all assets was around 35MB.

I can see it becoming a valid solution in the future, with all the tutorials and low entry we may see Godot run on coffee machines soon.