alt Hacker NewsIt's all from external pressure. Amazon spending energy on ebook DRM is a negative ROI activity for them.
A vanishingly small % of would-be ebook buyers even know pirated ones exist, and an even smaller one knows how to get those onto their Kindle.
My wife buys dozens of ebooks per year on Amazon, her friends too. I'm guessing if I poll that group, none of them would even know where to start, nor care to.
"Piracy is almost always a service problem" is also true. I see a lot of people who were risen on a pirated .mp3 and .epub to move to the streaming platforms just because it's a bit more convenient.