Good luck to them! Linux gaming has certainly made some strides. I don't think I'd bet my livelihood on selling a ton of these, but it is neat that somebody has decided to try.
On manufacturer's website [0], both the 15" and 17" Stellaris are listed with WQHD IPS-Panel (2560 x 1440 pixels) - I was looking at them just a few days ago.. The article lists 1080p as option, but it's not possible to order.
Games aren't just GPU-bound, either. Unreal says they develop their games on systems with "NVIDIA GeForce GTX 970" and "Six-Core Xeon E5-2643 @ 3.4GHz".
https://docs.unrealengine.com/4.27/en-US/Basics/InstallingUn...
A differently tuned CPU (more cores or higher base clock depending on the workload, less emphasis on boosting).
More RAM.
Higher resolution display could be nice, no need for 240fps.
Workstation rather than gaming graphics card.
That kind of explains the numpad.