That’s why. Right there.
Buttons add cost. A lot of cost.
Get rid of those, go all touchscreen, and $99 is achievable for Amazon.
Why does the new Kobo have a price $10 less than the new Nook?
Because the new Nook still has buttons. They don’t advertise them because that would defeat the “Simple Touch Reader” marketing message. But it has buttons flanking the sides, just as the original Nook and the above Kindle. Getting rid of those shaved $10 off the sales price of the Kobo.
So if getting rid of those minor buttons could crush an eInk device down to $129, don’t you think getting rid of all those Kindle buttons could get it down to $99? All those buttons look like a $40 price tax to me!