From a book market dynamics reality check
"Physical books today look like physical books of last century. And digital books of today look, feel, and function almost identically to digital books of 10 years ago, when the Kindle launched. The biggest change is that many of Amazon’s competitors have gone belly up or shrunken to irrelevancy. The digital reading and digital book startup ecosystem that briefly emerged in the early 2010s has shriveled to a nubbin.The 'Future Book' Is Here, but It's Not What We Expected | Wired
Amazon won. Trounced, really. As of the end of 2017, about 45 percent (up from 37 percent in 2015) of all print sales and 83 percent of all ebook sales happen through Amazon channels. There are few alternatives with meaningful mind- or market share, especially among digital books."