This is a screenless computer, meant to be used with XR/AR glasses or an external display. The Steam Deck motherboard goes in a 3d printed housing underneath the keyboard, giving you a keyboard that only needs to be connected to a display for a portable computer set up.
Here’s the hacker news discussion on it, includes comments from the creator of the project
Instead of a keyboard it should be the loudest most old fashioned typewriter possible, but still connected to AR glasses
just get cherry MX blue switches
Could connect it to a virtual boy display