Here is the poll I created:
https://www.mobileread.com/forums/sho...ight=bob_ninja
About 1/3 would like 2-3 or more years, but surprisingly are satisfied with only 1 year of use!?!!? Seems a lot of users are fickle and look to upgrade sooner. Still, as comments point out old devices are not thrown into garbage but sold on eBay to recover some value for purchasing a new version. Therefore most devices are used for well over 1 year.
The other failing of the study (which I don't have time to read, but based on conclusion is obvious) is that they didn't examine HOW MUCH content is actually consumed. My local newspapers are so bad that when I get them I read maybe 5% of their content AT MOST!!! Therefore, 95% of the paper production costs are pure waste.
If I did have a device like Kindle that automatically downloads certain newspapers, then I would have a far greater choice of newspapers and would likely select the ones that have content which appeals to me. I would probably read much more, 10%-20% of that content. Thus not only is energy of eNespaper delivery much lower (compared to printing pNewspapers) but I would also consume much more of it!!!
So the proper comparison would be how much energy is spent per UCI (unit of consumed information) for paper newspaper and for electronic newspaper.
Yeah, this conclusion is useless.