There seems to be real evidence[0] for the idea that focusing on nearby objects like computer screens for hours on end can contribute to the development of myopia. Breaks might help.
I don't see any reason to believe that making the screen transparent rather than looking to the side of it is a better way to look out a window for a break.
I want some VR goggles that are light, only do text, and have focus at infinity or so. Not just 3D convergence at infinity but somehow manage to blur just right so my eyes can focus on it like it's across the street. I'm not an optometrist I'm just a consumer and programmer. A guy can wish.
It’s impossible with near-eyes screens. See mismatch of vergence vs accomodation. The best thing for your eyes is to stay away from any head-mounted ar/vr/what-have-you-r stuff.
That's not what VAC is about. VAC is caused by the focus distance of a VR headset being fixed while convergence varies for each object to stimulate depth perception. There is no optical problem displaying text at infinity (both focus and convergence static at infinity) using a headset.
That's if you get motion sickness. You'd get temporary discomfort, not myopia. But if you don't get motion sickness, then AR/VR provides the benefit of a greater focal distance than computer monitors, tablets, smartphones, etc.
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 see any reason to believe that making the screen transparent rather than looking to the side of it is a better way to look out a window for a break.
[0] https://pubmed.ncbi.nlm.nih.gov/34622560/