As steady as any XR headset is. It's the same inside-out 6DOF tracking as Quest etc and feels just as stable.
I haven’t seen any device with the stability capabilities of Hololens 1 or 2. Would love to be proven wrong soon. The HLs use sensor fusion in hardware to adapt the current rendering at up to over 200 fps during device movement.
Maybe I just don't have your refined eye but I've assumed this was a solved problem for several years.
I also think a well encoded mp3 at around 192kbs VBR is good enough for everyone and nobody needs a 4k TV - so judge me as you see fit.
I'm asking primarily as I've seen people mention this as a non fully polished feature on the current array of XR glasses.
Hololens was ahead of its time. I have not used the Vision Pro much but suspect it's the closest and other headsets will start catching up in the next year or two