>>391664632
The only actual modular and free to tinker and combine VR infrastructure is SteamVR (And monado, but that's opensource collection of OpenXR frameworks and alternative drivers). The tech is even royalty free and ANYONE is allowed to create and sell SteamVR compatable devices. And yes, Knuckles are still the best VR controller ever invented.

Everything else is walled garden without interchangable parts.