(Audio books and ebooks were clearly larger changes than any 'book' changes still using paper. But with regards to journals you can not write or draw in those. And with regards to reading books or 'trade books,' audio and ebooks stopped gaining marketshare several years ago.)
So with regards to the NUE UX spine, "Why now?"
I believe there are several reasons.
First, even over centuries the paper book as a technology and a UX (user experience) does not see much change. Certainly not much radical change.
There are regular small technological changes (eg in glues) but I think the biggest UX changes next to mine were the paperback and the spiral. The paperback was invented around 1895 but it was not until WW2 that large military demand drove the resistive industry to change. In 1922 in France, Fischer was clearly and very creatively thinking about U and the UX when he invented the spiral. Super creative, right?
1895 and 1922. So significant change is not expected.
Nor is it sought. Aside from fonts and layouts, the industries' priorities have little to do with your usage and comfort: Their priorities are efficiencies, costs, and eliminating returns. So the glue goes on fast and thick.
Third, they also want to avoid risk. High volume binding machines can cost $2M.
Forth, there is a tremendous amount of 'culture' and tradition. During my years of R&D I spoke with some people that take pains to not break the spines. (Whereas I either thoroughly break them or I cut the spines off and convert them to spirals to make them stupid easy to read.)
Finally, I am from outside the industry, and regardless, I am prone to asking "Why not?" And I am typically freer from the many stale assumptions that many people unknowingly carry into their days. I found conventional books ridiculously hard to use and being an obsessive optimizer I found myself asking "Is that really as good as it can be?" And since I'm a geeky engineer, I reviewed the design and manufacturing assumptions. And I found a bad assumption.
Easy. Comfortable. Compliant. Adaptive. :)