Why does it need to be a new separate physical device, instead of just software installed on an old phone or laptop?
By all means the software will be open-source (and mostly off-the-shelf if possible) so anyone can install it on whatever device they have, but the killer product will be the Box.
How do you figure?
Also you may be interested in checking out https://kubesail.com/homepage and https://privaterouter.com/