Question Do I need Unity XR?

I want to make a game where it is possible to use a VR headset with controllers to play VR if you want.
But there are not much tutorials currently outside about that New unity xr and i dont even know, if I really need it for my game?

Because if I upload my game on steam later and I use the steamVr plugin from the unity asset store, do I still need the unity XR SDK if I want to make my game compatible with all VR Headsets Types?
Because I heard that Steam VR automatical supports all VR headset and if this rumor should be true, do I have to use unity XR?

So which is the most easiest way to let my game support all VR headset types and let the game still be playable with desktop, mouse and keyboard?

 

Do you plan to launch your game on oculus quest ?

If not, I think you can stick with steam VR but I wouldn't recommand it.
Unity will expand its XR SDK in the future and they will remove any other possibility in the near future.
It already began with Unity 2020.1

As for the second question, you will have to make two gameplay. One with VR on, and one without VR. It's not something related to XR SDK.

 

Can you please link me something in YouTube, where I can get started?
Because i have currently zero experience with unity VR and I use unity 2020.3 for my game.
My game should be playable with oculus, Windows mixed reality and vive. I dont need oculus quest and oculus store because that would be to much for me...
But it should be playable in a normal none-vr mode to for the case that the player dont got a VR or the player is to lazy to put VR on Like me sometimes...

I want to publish it on steam and that my game works well with VR on steam.