I think there are two main considerations in all this. It is true that ereaders with a capacative layer and a light guide layer are more fuzzy than those without. Not much. My eyes used to be good enough to tell the difference but only if I compared them carefully. It wasn't a difference I'd notice if it wasn't called to my attention.
The other consideration is that with the light today's ereaders have a lot better contrast. It really is like reading ink on paper and often better than ink on paper.
I think the light more than makes up for the small fuzziness it introduces. And today's ereaders have such high pixel density that I suspect they're sharper than the early readers without a light or touch layer.
The new Glowlight 3 is bringing this subject to the fore because it doesn't have a capacative layer, having an infra-red touch screen, and that reduces it's fuzziness by quite a bit, making it sharper than the competition. And since it's a 300 ppi screen with a good light it's contrast is good. All the reviewers mention how good it's screen looks and that's probably led to the comments you referred to.
I began reading on e-ink with the Kindle Keyboard, long before lights came along and before I knew there were touch screen readers. I was perfectly happy with it and couldn't see anything about it that could ever be improved. To me ereaders had been perfected had nowhere else to go. What a dummy I was.
Today's ereaders are far better. I wouldn't go back. I think maybe I'd like to have that new Glowlight 3 but I don't think that's a step back at all.
Barry