Not everyone gets motion sickness though. I can use my VR headset for hours without discomfort from VAC.

From that publication:

The results of the study indicated that the visual acuity of employees who work with data glasses generally did not change over the course of a shift and over a period of six months. Nevertheless, there were groups that had an increased chance of deterioration. Eye strain was frequently reported after working with the data glasses. Our study pointed out that employees aged 40 years and older are at risk for deteriorations of visual acuity, which is consistent with the findings of Yeow et al. (1991), who examined computer users.

I don’t understand why you keep bringing motion sickness.

When you want to see something at different distances, you not only change focus but also pivot eyes at a certain angle (towards the nose or not).

This angle is fucked with near-displays. And that inconsistency persists for hours.

It’s like you would use walking sim and your foot starts bending at not usual angles to accommodate some sick-built walking surface of the sim.