Folks it has been confirmed that the GPD Win 4 can run your Oculus Rift S and Oculus Quest VR.
I connected my Oculus Rift S and what do you know, it works. However, if you are going to connect an Oculus Rift S to your GPD Win 4 you will need to purchase a mini DVI to USB-C adapter.
I bet the GPD Win 4 will support other VR goggles.
Can a Steam Deck VR? Nope