Does anyone know how durable are the current e-ink readers? May it be so that Amazon moves away from e-ink readers in particular because they can't be made reli

Does anyone know how durable are the current e-ink readers? May it be so that Amazon moves away from e-ink readers in particular because they can't be made reliable? I like to read books and I was a theoretical fan of e-ink readers, but I never owned one. My younger brother, on the other hand, was against them: "why buy the device that only reads books?" On a recent trip to the countryside he borrowed a (PocketBook 301 plus) reader from a friend and put it in the tent's pocket together with a phone, iPod and other such stuff. In the morning, he found that the screen failed because it had a tiny crack. Maybe someone accidentally kicked it or something, but modern phones, iPod and such withstand abuse rather well, and this thing broke after one night - it even was in its own leather case that covers the screen! Googling revealed that cracking screen is a common issue. I start to suspect that those e-ink screen are a flawed technology as they are. There might be a reason Sony makes their readers with a metallic case, but do they last even then?