One of the most popular series on Kindle Unlimited right now is "A Shade of Vampire", which is comprised of 14 novels for a total of roughly 4,000 pages.
At the moment, a single fan binge-reading the entire series would make the author around $20—clearly on the low side, even if it's twice what a reader pays for a month of KU.
At one cent per page, that same genre-gorging glutton brings in about $40 for the author. A major improvement, and probably not unreasonable from Amazon's point of view—even if it means they're taking a sizable loss on subscribers like that.
In other words, if you write popular series of genre fiction novels, then the change will probably boost your income a fair bit.
Here are all the local Amazon links I could find:
Beep bloop. I'm a bot to convert Amazon ebook links to local Amazon sites. I currently look here: amazon.com, amazon.co.uk, amazon.ca, amazon.com.au, amazon.in, amazon.com.mx, amazon.de, amazon.it, amazon.es, amazon.com.br, amazon.nl, amazon.co.jp, amazon.fr, if you would like your local version of Amazon adding please contact my creator.