You're missing the biggest issue above all of them, comfort. VR headsets are not something you can wear for long gaming sessions. They get uncomfortable, sweaty, and your eyes absolutely need a break after a while.
It's only the first generation, akin to those giant blocky cellphones in the 90s. I manage one or two 2 hour sessions per day though. My wife and I just got out of a 2.5 hour one (https://www.twitch.tv/videos/125324129).
I've spent hours on Vive without a break screensharing in Bigscreen desktop with friends in other states or countries, and today I was playing paintball with people from Europe in Rec Room and went on a quest with a team from Dublin fighting dragons and an hour past without noticing. Vive is very comfortable for me when set up correctly.
Breaks really are important mostly because VR can be really taxing for your brain most certainly so for longer periods of play. With regards to comfort: I actually prefer the PSVR in that regard, for my anatomy the most comfortable headset so far.