I think we need to withhold analysis based on the 34 PPD number. In the article you can see that the rendering projection is quite distorted, with the apparent effect of using more pixels per degree for the center part. They don't account for this when calculating the 34 number. Of course a "fisheye" lens would also be "distorted" and allocate an equal number of pixels to each angle, so it's hard to tell by just eyeballing things. I wouldn't be surprised if the actual PPD number in the center, where it matters, is higher.
I think the article merely superimposed manually distorted screenshots from the AVP onto a photo of the sensor, rather than taking a photo of the sensor while turned on, so it's not representative of the distortion, but yes, I agree, you make a good point - the pancake lens optics might be nonlinear, with higher PPD in the center.
He concludes, by making comparison with the Meta Quest which has similar pancake optics to the AVP, and by scaling up the PPD, that the AVP's PPD could be as high as 39 PPD in the center of the image.
I think most of the conclusions derived from the analysis here will still hold true if the central PPD does turn out to be as high as 39, rather than 34. It's still a very long way from 20/20 retina at 60, from foveal cone density at 110, and pales in comparison to the PPD achieved by even entry level 14" laptops or 27" 4K displays.
