[fadeyev]

I think his point is that low DPI devices don't render detailed fonts well so we're forced to use fonts that are optimized for the screen (Verdana, Georgia, etc) if we want to see decent results (i.e. not a blurry mess). Because these fonts are optimized for low pixel density they tend to be pretty simple and boring, or at least not as rich and expressive as they can be if there was no resolution constraint. As a result of using simpler fonts designers compensate by adding additional details to the interface in the form of skeuomorphic effects. Yes, the effects also often communicate function, but they also act as decorations that make the interface more interesting to look at.

Now, on HiDPI displays we can go back to using more detailed fonts that we use in print without loss of quality, so the text part of the interface gains a lot in aesthetics and character, so much so that we no longer need all the stuff around the text to make it look good.

Additionally, because HiDPI displays are able to show that much more detail, it is a lot more difficult for designers to create skeuomorphic interfaces that look believable. The crudeness of the old displays helped mask the simplicity and lack of realism of the skeuomorphic design. Our eyes and mind knew that what was being represented is not real, just an impression, and so we evaluate it as an impression, not as something real. On contrast, HiDPI resolution is so high that what's being represented actually looks real, but if the smaller detail is off the effect of realism is lost, so the overall thing ends up looking like a poor fake rather than a good impression.