There is work[1] to address focal issues, and obviously resolution will continue to get better. I notice the focal issues in VR racing sims when I glance between my mirrors and back to the track, you expect a shift in focal length and it hurts your brain when there is none.

I'm still excited to see where HMDs get to in the next 5-10 years, both AR and VR.

Oculus Research' 'Focal Surface Display'

1: https://www.youtube.com/watch?v=W7JjANVKINA