First, note I said VR/AR, so not everyone needs a headset. Many workloads will work in AR, though the black pixel problem means these will be much harder to crack and so will probably arrive later.
But I think once the VR headsets get miniaturized a bit more (give it a generation or three) people will laugh when they think about the current models, just like we do about cell phones vs. the first satellite phones that were bigger than your head. At some point these will be as light as a pair of plastic sunglasses or goggles.
There is nothing forcing you to use VR for something like a call, where you don’t currently need a monitor. But I think we’ll see a tipping point where the face tracking gets across the canny valley and people stop saying “you need to meet someone in person to really connect”. At that point VR calls substitute for in-person meetings, not VCs on a screen.
Consider the move to remote work; if we can get a virtual meeting room to feel like whiteboarding in person, including gaze and expression detection, then you could bounce between meeting room with your distributed team and perfect immersive dev setup without leaving your seat.
For the median worker using a monitor I think the requirements to beat monitors are just good enough resolution for spreadsheets/email (we may be there next gen?), comfort (currently the crux), and a decent story on input passthrough (your physical keyboard rendered in VR? Something else? Seems tractable, we just haven’t standardized any options.)